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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

A new look at the first dinosaur discovered in Antarctica: reappraisal of Antarctopelta oliveroi(Ankylosauria: Parankylosauria)

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Advances in Polar Science 2024年

作者： Sergio SOTO ACU?A Alexander O.VARGAS Jonatan KALUZA Consejo Nacional de Investigaciones Científicas y Técnicas (conicet) Red Paleontológica U-Chile，Departamento de Biología， Facultad de Ciencias， Universidad de Chile Fundación de Historia Natural Félix de Azara， Universidad Maimónides Escuela de Geología，Facultad de Ciencias， Ingeniería y Tecnología， Universidad Mayor， Providencia

The first dinosaur discovered in the Antarctic continent was the ankylosaur Antarctopelta oliveroi in the 1980s. Nevertheless， since then several hypotheses of phylogenetical relationships have been proposed because these have been depended on how the skeletal remains have been interpreted. The main obstacle for clarifying its phylogenetic position is that many portions of the skeleton remain unknown， in addition to the presence of unknown characters in typical ankylosaurs. Considered an ankylosaurid， nodosaurid， or even a chimaera， a recent proposal based on mostly complete material of a new ankylosaur from Chilean Patagonia provided support for a novel phylogenetic hypothesis: Antarctopelta and other southern ankylosaurs are an early branching clade， the Parankylosauria， whose origin probably dates to the Late Jurassic. In the light of this new view， a redescription of the available skeletal remains is provided together with a new reconstruction of the first Antarctic dinosaur known to the science community.

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Principal Equatorial Null Geodesic Congruences in the Kerr Metric, and Their Quantum Propagators

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Journal of High Energy Physics, Gravitation and Cosmology 2024年第3期10卷 906-917页

作者： Josué G. Mateos Trujillo Miguel Socolovsky Instituto de Ciencias Nucleares Universidad Nacional Autnoma de Mxico Cd. Universitaria Ciudad de Mxico Mxico Instituto de Astronoma y Fsica del Espacio Universidad de Buenos Aires-CONICET Ciudad de Buenos Aires Argentina

Using the Raychaudhuri equation, we associate quantum probability amplitudes (propagators) to equatorial principal ingoing and outgoing null geodesic congruences in the Kerr metric. The expansion scalars diverge at the ring singularity;however, the propagators remain finite, which is an indication that at the quantum level singularities might disappear or, at least, become softened.

关键词： Kerr Metric Principal Null Geodesics Propagators

Grazing Pressure and Plant Functional Types in Puna Highlands,Northwestern Argentina

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Phyton-International Journal of Experimental Botany 2024年第5期93卷 1067-1080页

作者： Quiroga Mendiola Mariana Tálamo Andrés IPAF NOA—INTA(National Institute for Agricultural Technology) Posta de HornillosJujuy4622Argentina Facultad de Ciencias Naturales Universidad Nacional de SaltaSalta4400Argentina Instituto de Bio y Geociencias del NOA(IBIGEO) UNSa-CONICET.Laboratorio de Ecología Aplicada a la Conservación(LEAC)Facultad de Ciencias NaturalesUniversidad Nacional de SaltaSalta4400Argentina Maestría en Gestión Ambiental Escuela de NegociosUniversidad Católica de Salta(UCASAL)Salta4400Argentina

The Puna grasslands support grazing systems that produce meat and wool in multi-species herds,especially from llama(Lama glama)and ***,it is yet unknown whether grazing pressure can modify grassland structure and Plant Functional Types diversity and cover in Puna *** analyzed the relationship between grazing pressure and Plant Functional Types by comparing transects located near stockyards(high grazing pressure)and far from them(low pressure)and by evaluating the relationship between the Plant Functional Types cover to a Grazing Pressure Index(GPI).This index incorporates the heterogeneity of traditional pastoral *** two ecological sites(Ciénego and Tolar),we sampled paired transects(near-far).Plots near and far from corrals were similar in all the variables measured except for plots in Tolar,which tend to have higher total cover,possibly due to fecal fertilization near ***,we recorded an increase in total cover and grass cover at higher GPI in Ciénego,while in Tolar we found lower values of total cover and herbaceous dicotyledonous cover at intermediate intensities of *** only negative relationship found was the cover of clonal and non-clonal shrubs,possibly explained by the greater use of these shrubs as firewood near *** summary,our study does not show important changes in Plant Functional Types as a function of grazing pressure in the studied grasslands probably because grazing pressure is diluted or diminished when livestock rotates in different areas and grazing durations ***,the long grazing history with which the Puna has evolved could also contribute to the co-structuration between native vegetation and livestock farming.

关键词： Natural grasslands Puna herbivory ecological perturbation

Response of ants to grazing disturbance at the central Monte Desert of Argentina: community descriptors and functional group scheme

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Journal of Arid Land 2014年第1期6卷 117-127页

作者： Silvia CLAVER Susana L SILNIK Florencia F CAMPóN Entomology Lab IADIZA-CONICET

Livestock ranching is one of the main productive activities in arid regions of the *** produces changes in animal as well as plant communities(***,abundance and species dominance relationships).Ants are good biological indicators due to the environmental fidelity of some of their community *** described the functional structure of the ant community in the central Monte of Mendoza,Argentina,and examined the effect of grazing using richness,diversity and the functional group *** used pitfall traps to sample ants at a reserve with 30-year cattle exclusion and at an adjacent *** of the 27 recorded species showed significant differences in their abundance and two species were absent at the *** richness and diversity did not reflect these differences,functional groups *** Climate Specialists were more abundant at the ranch while Cryptic Species and Generalized Myrmicinae increased at the *** study supports the utility of the functional group scheme to study the effects of grazing disturbance in ant communities of arid regions.

关键词： ants cattle grazing functional groups richness diversity arid zones Monte Desert

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1990-2020年阿根廷门多萨流域冰川变化研究

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中国农村水利水电 2024年第5期 78-86页

作者：林媛媛王飞戈文艳韩剑桥 Fidel Alejandro Roig Elena María Abraham 陈昊西北农林科技大学水土保持科学与工程学院陕西杨凌712100 中国科学院水利部水土保持研究所陕西杨凌712100 Instituto Argentino de Nivología Glaciología y Ciencias Ambientales(IANIGLA-CONICET)CCT MendozaArgentina5500 Instituto Argentino de Investigaciones de Las Zonas Áridas(IADIZA-conicet) CCT MendozaArgentina5500

冰川是南美洲阿根廷门多萨流域(33°S)重要的淡水资源,冰川作为气候变化的敏感指示器,对于理解和评估全球和区域气候变化具有重要意义。为了解门多萨流域冰川分布及变化趋势,探讨其对区域水资源和生态系统的影响,为应对气候变化提供科... 详细信息

冰川是南美洲阿根廷门多萨流域(33°S)重要的淡水资源,冰川作为气候变化的敏感指示器,对于理解和评估全球和区域气候变化具有重要意义。为了解门多萨流域冰川分布及变化趋势,探讨其对区域水资源和生态系统的影响,为应对气候变化提供科学依据,研究基于1990-2020年Landsat遥感影像,参考RGI冰川编目数据和阿根廷国家冰川清单,通过比值阈值法和人工解译法得到7期冰川边界,研究了门多萨流域冰川面积分布与变化特征。并结合TerraClimate气候数据,揭示了该区域在研究期间的气候变化趋势,探讨了区域气候变化对冰川变化的影响。结果表明:①2020年门多萨流域冰川面积为134.09±11.86 km^(2),1990-2020年冰川总体呈极显著波动下降趋势(p10 km^(2)占比最大,10 km^(2)规模冰川退缩速度最大;冰川主要分布在南坡,西北坡冰川最少,东南、东北坡冰川退缩速度最大;冰川主要分布在坡度5°~40°之间,50°~55°的冰川退缩速度最大;冰川主要分布在海拔4200~5400 m之间,<4000 m冰川退缩速率最大。③20世纪50年代末以来门多萨地区气温整体呈现极显著的上升趋势(p<0.001),研究区年均最高、最低气温每十年上升0.53、0.29℃。气温持续上升是门多萨流域冰川退缩的长期原因,降水变化是该区域冰川变化的短期原因。本研究为门多萨流域预防冰川变化导致的水资源可用性变化和地质灾害预防提供参考。

关键词：冰川变化门多萨(Mendoza) 南美洲气候变化

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Characterization of Arroyo Verde Epithermal Deposit:Paragenesis,Mineral Geochemistry,Geochronology and Fluid Inclusions in Lower Chon Aike Volcanism,Argentina

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Journal of Earth Science 2024年第1期35卷 62-84页

作者： Cecilia Pavón Pivetta Leonardo Benedini Paulo Marcos Ma.Agustina Cócola Mercedes Virginia Barros Daniel Gregori Leonardo Strazzere Anderson Costa dos Santos Mauro C.Geraldes Instituto Geologico del Sur(INGEOSUR) Universidad Nacional del Sur(UNS)-Consejo Nacional de Investigaciones Cientificas y Tecnicas(CONICET)Bahia Blanca 8000Argentina Dpto.de Geologia Universidad Nacional del Sur(UNS)Bahia Blanca 8000Argentina Universidad Nacional de Rio Negro Instituto de Investigacion en Paleobiologia y GeologiaGeneral Roca 8332Argentina Universidade do Estado do Rio de Janeiro Faculdade de GeologiaDepartamento de Mineralogia e Petrologia igneaRiodeJaneiro20559-900Brazil Geobiotec Departamento de GeocienciasUniversidade de AveiroAveiro 3800-002Portuga

Arroyo Verde epithermal deposit,in the North Patagonia region of Argentina,is located within the Lower Chon Aike volcanism and is developed between 192.6±2.5 Ma(mineralization host rock)and 189.5±2.6 Ma(overlying lava).Marifil volcanic complex is the host rock for these veins,veinlets and *** particular small deposit has developed low to intermediate sulphidation characteristics,with gangue mineral textures associated with several ore *** probe microanalysis determines electrum,silver minerals such as acanthite,and tetrahedrite,related Ag-Cu minerals like jalpaite,mckinstryite,stromeyerite,and base metals like chalcopyrite,sphalerite,galena and *** inclusions in quartz of two out of five events indicate that these Low Jurassic veins were formed due to subtle boiling and dilution mechanisms and by low-salinity(3.4 wt.%to 6.7 wt.%NaCl Eq)magmatic-hydrothermal fluid at 225 to 310℃.The fluid inclusion measurements that indicate boiling(Event 3)were plotted,and based on this data,we interpret that the Arroyo Verde deposit has been eroded between 550 and 700 *** particular character has not been previously recorded for other sectors of the eastern north Patagonian region.

关键词： epithermal deposit Ag minerals mineral geochemistry fluid inclusions Chon Aike geochronology

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Typhoon-and pollution-driven enhancement of reactive bromine in the mid-latitude marine boundary layer

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National Science Review 2024年第4期11卷 93-101页

作者： Shanshan Wang Qinyi Li Ruifeng Zhang Anoop Sharad Mahajan Swaleha Inamdar Nuria Benavent Sanbao Zhang Ruibin Xue Jian Zhu Chenji Jin Yan Zhang Xiao Fu Alba Badia Rafael P.Fernandez Carlos A.Cuevas Tao Wang Bin Zhou Alfonso Saiz-Lopez Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention (LAP3) Department of Environmental Science and Engineering Fudan University Institute of Eco-Chongming(IEC) Department of Atmospheric Chemistry and Climate Institute of Physical Chemistry Blas CabreraCSIC Department of Civil and Environmental Engineering The Hong Kong Polytechnic University Environment Research Institute Shandong University Centre for Climate Change Research Indian Institute of Tropical MeteorologyMinistry of Earth Sciences Department of Chemistry University of Colorado Boulder Institute of Environment and Ecology Tsinghua Shenzhen International Graduate SchoolTsinghua University Sostenipra Research Group Institute of Environmental Science and Technology(ICTA)Universitat Autonoma de Barcelona(UAB) Institute for Interdisciplinary Science (ICB) National Research Council (CONICET)

Tropospheric reactive bromine is important for atmospheric chemistry,regional air pollution,and global *** studies have reported measurements of atmospheric reactive bromine species in different environments,and proposed their main sources,***-salt aerosol（SSA）,oceanic biogenic activity,polar snow/ice,and *** and other strong cyclonic activities（***） induce abrupt changes in different earth system processes,causing widespread destructive ***,the role of typhoons in regulating reactive bromine abundance and sources remains ***,we report field observations of bromine oxide（BrO）,a critical indicator of reactive bromine,on the Huaniao Island（HNI）in the East China Sea in July *** observed high levels of BrO below 500 m with a daytime average of9.7±4.2 pptv and a peak value of ～26 pptv under the influence of a *** field measurements,supported by model simulations,suggest that the typhoon-induced drastic increase in wind speed amplifies the emission of SSA,significantly enhancing the activation of reactive bromine from SSA *** also detected enhanced BrO mixing ratios under high NOxconditions（ppbv level） suggesting a potential pollution-induced mechanism of bromine release from *** elevated levels of atmospheric bromine noticeably increase ozone destruction by as much as ～40% across the East China *** the high frequency of cyclonic activity in the northern hemisphere,reactive bromine chemistry is expected to play a more important role than previously thought in affecting coastal air quality and atmospheric oxidation *** suggest that models need to consider the hitherto overlooked typhoon-and pollution-mediated increase in reactive bromine levels when assessing the synergic effects of cyclonic activities on the earth system.

关键词： reactive bromine atmospheric chemistry marine boundary layer atmospheric oxidation capacity marine emission

Interindividual Age-Independent Differences in Human CX43 Impact Ventricular Arrhythmic Risk

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Research 2024年第3期6卷 417-432页

作者： Laura García-Mendívil María Pérez-Zabalza Antoni Oliver-Gelabert JoséMaría Vallejo-Gil Javier Fañanás-Mastral Manuel Vázquez-Sancho Javier AndréBellido-Morales Alexánder Sebastián Vaca-Núñez Carlos Ballester-Cuenca Emiliano Diez Laura Ordovás Esther Pueyo Biomedical Signal Interpretation and Computational Simulation group(BSICoS) Aragón Institute of Engineering ResearchUniversity of ZaragozaZaragoza 50018Spain BSICoS Instituto de Investigación Sanitaria Aragón(IISA)Zaragoza 50018Spain Centro Universitario de la Defensa(CUD) Zaragoza 50090Spain. Department of Cardiovascular Surgery University Hospital Miguel ServetZaragoza 50009Spain. Institute of Experimental Medicine and Biology of Cuyo(IMBECU) CONICETMendoza 5500Argentina. Fundación Agencia Aragonesa para la Investigación y el Desarrollo(ARAID) Zaragoza 50018Spain. Biomedical Research Networking Center in Bioengineering Biomaterials and Nanomedicine(CIBER-BBN)Zaragoza 50018Spain.

Connexin 43 (CX43) is one of the major components of gap junctions, the structures responsible for the intercellular communication and transmission of the electrical impulse in the left ventricle. There is limited information on the histological changes of CX43 with age and their effect on electrophysiology, especially in humans. Here, we analyzed left ventricular biopsies from living donors starting at midlife to characterize age-related CX43 remodeling. We assessed its quantity, degree of lateralization, and spatial heterogeneity together with fibrotic deposition. We observed no significant age-related remodeling of CX43. Only spatial heterogeneity increased slightly with age, and this increase was better explained by biological age than by chronological age. Importantly, we found that CX43 features varied considerably among individuals in our population with no relevant relationship to age or fibrosis content, in contrast to animal species. We used our experimental results to feed computational models of human ventricular electrophysiology and to assess the effects of interindividual differences in specific features of CX43 and fibrosis on conduction velocity, action potential duration, and arrhythmogenicity. We found that larger amounts of fibrosis were associated with the highest arrhythmic risk, with this risk being increased when fibrosis deposition was combined with a reduction in CX43 amount and/or with an increase in CX43 spatial heterogeneity. These mechanisms underlying high arrhythmic risk in some individuals were not associated with age in our study population. In conclusion, our data rule out CX43 remodeling as an age-related arrhythmic substrate in the population beyond midlife, but highlight its potential as a proarrhythmic factor at the individual level, especially when combined with increased fibrosis.

关键词： CX43 rhythm Independent