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Carbon pool dynamics after variable retention harvesting in Nothofagus pumilio forests of Tierra del Fuego

Ecological Processes 2023年第1期12卷 64-82页

作者： Jimena E.Chaves marie-claire aravena acuña Julián Rodríguez-Souilla Juan M.Cellini Nolan J.Rappa María V.Lencinas Pablo L.Peri Guillermo J.Martínez Pastur Centro Austral de Investigaciones Científicas(CADIC) Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET)Houssay 200(9410)UshuaiaTierra del FuegoArgentina Laboratorio de Investigaciones en Maderas(LIMAD) Universidad Nacional de la Plata(UNLP)Diagonal 113469(1900)La PlataBuenos AiresArgentina Nature Conservation&Landscape Ecology University of FreiburgTennenbacherstrasse 479106 FreiburgGermany Instituto Nacional de Tecnología Agropecuaria(INTA) Universidad Nacional de la Patagonia Austral(UNPA)Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET)Cc 332(9400)Río GallegosSanta CruzArgentina

Background It is necessary to determine the implications for managing forest stands using variable retention harvesting for maintaining carbon and for calculating the effects of different harvesting practices on above-and below-ground carbon balance in forest *** this context,forest carbon management has gained more attention among managers and policy-makers during recent *** aim of this study was to determine carbon pool dynamics in different forest ecosystem components after variable retention harvesting(VRH)to characterize the ecological stability and quantify the recovery rate through the years-after-harvesting(YAH).Methods Carbon pool compartmentalization of 14 different components was determined in 60 harvested and primary unmanaged forests during the first 18 YAH in Tierra del Fuego(Argentina).We compared them using uni-and multi-variate methods,relativizing the outputs with primary unmanaged *** We determined the effectiveness to retain carbon components in post-harvested stands under different retention strategies(aggregated ***).The balance among carbon pool components changed between managed and unmanaged stands across the YAH,and was directly related to the impact *** retention improved the ecological stability of the harvested areas,where the below-ground components were more stable than the above-ground *** recovery rate was directly related to the post-harvesting natural dynamics of the *** studied period was not enough to fully recover the C levels of primary unmanaged for-ests,but VRH showed advantages to increase the C pools in the managed *** Promoting VRH can improve sustainable forestry at the landscape level and in the long term,generating positive synergies with biodiversity and the provision of ecosystem *** study provides important new insights into forest carbon management,in particular to setting standards in carbon projects and sets the ground

关键词： Carbon reservoir Temperate forest Ecological stability Recovery rate Forest carbon management

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A NEW STATISTICAL APPROACH FOR THE ANALYSIS OF UNCERTAIN SYSTEMS

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Journal of Systems Science & Complexity 2009年第1期22卷 1-34页

作者： Xinjia CHEN Kemin ZHOU Jorge aravena Department of Electrical Engineering Southern University Baton Rouge LA 70813 USA. Department of Electrical and Computer Engineering Louisiana State University Baton Rouge LA 70803 USA.

This paper addresses the issues of conservativeness and computational complexity of probabilistie robustness analysis. The authors solve both issues by defining a new sampling strategy and robustness measure. The new measure is shown to be much less conservative than the existing one. The new sampling strategy enables the definition of efficient hierarchical sample reuse algorithms that reduce significantly the computational complexity and make it independent of the dimension of the uncertainty space. Moreover, the authors show that there exists a one to one correspondence between the new and the existing robustness measures and provide a computationally simple algorithm to derive one from the other.

关键词： Computational complexity randomized algorithms risk analysis robustness analysis uncertain system.

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Gene abundances of AOA,AOB,and anammox controlled by groundwater chemistry of the Pearl River Delta,China

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China Geology 2021年第3期4卷 463-475页

作者： Kun Liu Xin Luo Jiu Jimmy Jiao Ji-dong Gu Ramon aravena Department of Earth Sciences Faculty of ScienceThe University of Hong KongHong Kong 999077China Department of Ecology and Biodiversity School of Biological SciencesThe University of Hong KongHong Kong 999077China Department of Earth and Environmental Sciences University of WaterlooWaterloo N2L 3G1Canada China Institute of Geo-Environment Monitoring China Geological SurveyBeijing 100081China

Ammonia-oxidizing archaea(AOA),ammonia-oxidizing bacteria(AOB),and anaerobic ammonia-oxidation(anammox)bacteria are very important contributors to nitrogen cycling in natural *** gene abundances of these microbes were believed to be well relevant to N-cycling in groundwater systems,especially in the Pearl River Delta(PRD)groundwater with unique high intrinsic ammonia *** this research,20 sediment samples from two in the PRD were collected for porewater chemistry analysis and quantification of N-cycling related genes,including archaeal and bacterial amoA gene and anammox 16S ribosomal Ribonucleic Acid(rRNA)*** Polymerase Chain Reaction(qPCR)results showed that gene abundances of AOA,AOB,and anammox bacteria ranged from 3.13×10^(5)to 3.21×10^(7),1.83×10^(4)to 2.74×10^(6),and 9.27×10^(4)to 8.96×10^(6)copies/g in the sediment of the groundwater system,*** bacteria and AOA dominated in aquitards and aquifers,respectively,meanwhile,the aquitard-aquifer interfaces were demonstrated as ammonium-oxidizing hotspots in the aspect of gene *** abundances of nitrifiers were analyzed with geochemistry *** between gene numbers and environmental variables indicated that the gene abundances were impacted by hydrogeological conditions,and microbial-derived ammonium loss was dominated by AOA in the northwest PRD and by anammox bacteria in the southeast PRD.

关键词： Anammox Ammonium oxidizing archaea(AOA) Ammonium oxidation bacteria(AOB) Aquitard Groundwater Hydrogeological survey engineering Pearl River Delta China

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For a Micro-Politics Analysis of Engineering Education

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Journal of Philosophy Study 2014年第8期4卷 574-589页

作者： Jose aravena-Reyes Federal University of Juiz de Fora

The idea that studies about education for engineers should be complemented with micro-politics analysis which is presented in this article. For such, we present a framework to conceptualizing micropolitics and some elements that show how the micro- and macro-politics are overlapped in any political fact. From this premise, the micro-politics is used to lift some elements of analysis of a particular case of engineering educational process in Brazil, where several dominant behaviors are characterized as violent or repressive behaviors that do not favor the development of technical inventivity, one of fundamental characteristics of the profession. What is argued here is that these behaviors are part of the range of a dominant subjectivity that has as its goal the maintenance of professional subjectivity not to develop in students a critical subjectivity, which must be produced under teaching techniques and pedagogical approaches. To consolidate the micro-politics analysis perspective are cited several statements used in Brazilian engineering education process, which diverts attention from the real reasons for failures in the engineers＂ education. Finally, a report of physics violence inside a Brazilian public institution is cited to illustrate how the coercive institutional power operates in the production of students＇ subjectivity.

关键词： micro-politics engineering education subjectivity production

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Extreme drought triggers parallel shifts in wood anatomical and physiological traits in upper treeline of the Mediterranean Andes

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Ecological Processes 2024年第1期13卷 132-143页

作者： Luiz Santini Jr. Dylan Craven Daigard Ricardo Ortega Rodriguez Manolo Trindade Quintilhan Stephanie Gibson-Carpintero Cristina aravena Torres Fidel A.Roig Ariel A.Mu?oz Alejandro Venegas-Gonzalez Hémera Centro de Observación de la Tierra Universidad Mayor GEMA Center for Genomics Ecology and Environment Universidad Mayor Data Observatory Foundation ANID Technology Center Depart-ment of Forest Sciences ESALQ-University of Sao Paulo Department of Plant Biology Institute of Biology University of Campinas Instituto de Geografía Universidad Nacional Autónoma de México (UNAM) Argentine Institute of Nivology Glaciology and Environmental Sciences(IANIGLA CONICET ) Institute of Geography Pontificia Universidad Católica de Valparaíso Instituto de Ciencias Agroalimentarias Animales y Ambientales (ICA3) Universidad de O'Higgins

Background Treeline ecotones of Mediterranean ecoregions have been affected by the increasing intensity and severity of droughts. Even though the effect of droughts on forest dynamics has been widely documented, knowledge is relatively scarce of how extreme climate episodes affect the hydraulic structure and, therefore, the phys-iology of woody plants. The Mediterranean Andes have experienced an uninterrupted period of drought since 2010, including an extremely dry year in 2019 with approximately 80% rainfall deficit. Here, we investigated shifts in wood anatomical and physiological traits of Kageneckia angustifolia, an endemic treeline species, in response to this drought *** We evaluated the xylem plasticity of three K. angustifolia populations across their natural distribution(31–35° SL) based on anatomical(vessel structure and distribution) and physiological(intrinsic water-use efficiency) variables in the tree rings. We focused on the period 2000–2020 that corresponds to before the megadrought(2000–2007),(ii) megadrought(2008–2018) and(iii) hyperdrought(2019–2020). The variables were annualized and analyzed by linear mixed-effects *** Our results provide insights to the anatomical and physiological mechanisms underlying the resilience of treeline forests to persistent droughts in central Chile. We found that the extreme drought in 2019–2020 triggered shifts in vessel size and frequency that increased hydraulic safety. These significant shifts in vessel traits occurred in parallel with a decrease in pit aperture area and an increase in water-use efficiency, further increasing the resilience of K. angustifolia to extreme drought *** Our results revealed coordinated shifts in vessel size and frequency and water-use efficiency in response to the megadrought, thereby reducing vulnerability to hydraulic failure. The apparent resilience of K. angustifolia to extreme droughts suggests that this adaptation to drought stress may incre

关键词： Dendro-anatomy Kageneckia angustifolia Xylem vulnerability Drought Climate change

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论大数据背景下金融合规管理中的隐私问题及其伦理对策

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财经理论与实践 2021年第1期42卷 2-9页

作者：吕耀怀 Paula Andrea aravena 杭州师范大学公共管理学院浙江杭州311121 智利大学经济与商业学院智利圣地亚哥7561160

大数据技术在金融领域的广泛应用,一方面,改善了金融服务;另一方面,由于大数据技术自身的属性而可能导致更多、更大的隐私风险。在这种背景下,金融领域的合规管理面临双重的隐私风险:一是金融实体之业务活动所可能产生的隐私风险,二是... 详细信息

大数据技术在金融领域的广泛应用,一方面,改善了金融服务;另一方面,由于大数据技术自身的属性而可能导致更多、更大的隐私风险。在这种背景下,金融领域的合规管理面临双重的隐私风险:一是金融实体之业务活动所可能产生的隐私风险,二是合规管理自身所可能产生的隐私风险。因此,为了应对金融领域中合规管理所可能遭遇的隐私问题,也就需要有两个方面的伦理对策:一是针对金融实体全部业务活动中隐私风险的伦理对策,二是针对有权接触、利用金融客户数据、信息的合规管理人员的伦理对策。除了基本的伦理对策之外,为了使得柔性的伦理对策不至于成为花瓶般的摆设,有必要为其设置相应的制度保障。

关键词：大数据金融合规隐私伦理

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Genome of a thermophilic bacterium Geobacillus sp. TFV3 from Deception Island, Antarctica

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Advances in Polar Science 2020年第2期31卷 146-152页

作者： Xin Jie CHING Chui Peng TEOH Dexter J.H.LEE Marcelo GONZáLEZ-aravena Nazalan NAJIMUDIN Yoke Kqueen CHEAH Paris LAVIN Clemente Michael Vui Ling WONG Biotechnology Research Institute Universiti Malaysia SabahJalan UMS88400 Kota KinabaluSabahMalaysia Instituto Antártico Chileno Plaza Munoz Gamero 1055Punta ArenasChile School of Biological Science Universiti Sains MalaysiaPersiaran Bukit Jambul 11900 Bayan LepasPenangMalaysia Department of Biomedical Science Faculty of Medicine and Health SciencesUniversiti Putra Malaysia43400 UPM SerdangSelangor Darul EhsanMalaysia Universidad de Antofagasta Facultad de Ciencias del Mary Recursos BiologicosDepartamento de BiotecnologiaLaboratorio de Complejidad Microbianay Ecología FuncionalInstituto AntofagastaChile National Antarctic Research Centre University of Malaya50603 Kuala LumpurMalaysia

Thermophilic microorganisms have always been an important part of the ecosystem,particularly in a hot environment,as they play a key role in nutrient recycling at high temperatures where most microorganisms cannot *** most of the thermophiles are archaea,thermophiles can also be found among some species of *** bacteria are very useful in the fundamental study of heat adaptation,and they are also important as potential sources of thermostable enzymes and ***,we have isolated a Gram-positive thermophilic bacterium,Geobacillus ***3 from a volcanic soil sample from Deception Island,*** project was undertaken to analyze the genes of this thermophilic Antarctic bacterium and to determine the presence of thermal-stress adaptation proteins in its *** genome of Geobacillus ***3 was first purified,sequenced,assembled,and *** complete genome was found to harbor genes encoding for useful thermal-stress adaptation *** majority of these proteins were categorized under the family of molecular chaperone and heat shock *** genomic information could eventually provide insights on how the bacterium adapts itself towards high growth temperatures.

关键词： temperature 16SrDNA genomes Geobacillus Deception Island

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“正确原型”住宅

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城市环境设计 2010年第Z2期 275-277页

作者： Alejandro aravena

第一,在恶劣情况下的幸存者,实现了他们作为人的潜力,增强了意识并锻炼了品格。难怪这些社区是何等的骄傲,也难怪究竟是成为了他们最大的财富。这意味着,人民应该有一个家,与这个新身份相匹配,并拥有能够利用这一潜力的能力。第一步,是... 详细信息

第一,在恶劣情况下的幸存者,实现了他们作为人的潜力,增强了意识并锻炼了品格。难怪这些社区是何等的骄傲,也难怪究竟是成为了他们最大的财富。这意味着,人民应该有一个家,与这个新身份相匹配,并拥有能够利用这一潜力的能力。第一步,是要做到正确无误!并在道路的尽头,我们将会取得更好的成绩。所以,我们设计的房子被一个更广阔的视野出发点的家庭可以在其中发展和表达自己的能力。

关键词：房子定义

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