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Quality evaluation of Nothofagus pumilio seeds linked to forest management and climatic events

Ecological Processes 2024年第1期13卷 98-107页

作者： Julian Rodríguez-Souilla Jimena E.Chaves María Vanessa Lencinas juan manuel cellini Fidel A.Roig Pablo L.Peri Guillermo Martinez Pastur Laboratorio de Recursos Agroforestales Centro Austral de Investigaciones Científicas (CADIC) Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET ) Laboratorio de Investigaciones en Maderas (LIMAD) Universidad Nacional de la Plata (UNLP) Instituto Argentino de Nivología Glaciología y Ciencias Ambientales (IAN-IGLA) Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Instituto Nacional de Tecnología Agropecuaria (INTA) Universidad Nacional de la Patagonia Austral (UNPA) Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET )

Background Forest ecosystems undergo significant transformations due to harvesting and climate fluctuations, emphasizing the critical role of seeding in natural regeneration and long-term structural preservation. Climate change further amplifies these dynamics, affecting phenology across species and regions. In Tierra del Fuego(Argentina), Nothofagus pumilio(lenga) forests represent the most important timber resource, and it is managed through different silvicultural strategies. This species demonstrates notable post-disturbance regeneration, yet seed fall exhibits signifi-cant variability, leading to variations in seed quality(e.g., viability). This study aims to assess fluctuations in N. pumilio seed quality, determine how it varies concerning forest management strategies, annual productivity, and the co-occurrence of climatic phenomena including El Ni?o-Southern Oscillation(ENSO) and the Southern Annular Mode(SAM).Results Viable seeds represented 18.4% of the total, notably higher in unharvested than in managed areas. Con-versely, empty seeds were more prevalent in harvested areas(> 75%). Seed quality exhibited significant differences across silvicultural treatments, except for insect-predated seeds, which had similar proportions across all areas, though dispersed retention showed higher predation. When considering years with varying production levels, high-production years favoured full and viable seeds, particularly in unharvested forests and aggregated retention, while low-production years saw reduced viability across all treatments. Quadratic models revealed that viability increased with seed production, where unharvested forests achieved the highest values. Climate variability influenced seed proportions, where ENSO+/SAM+ promoting more full and viable seeds, while ENSO–/SAM+ favoured non-predated seeds, especially in unharvested *** Seed quality varies among treatments and years with different levels of seeding. Variations in seed qual-ity, l

关键词： Forest management Seeding Climate change Extreme event Patagonia

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Soil organic carbon stocks in native forest of Argentina:a useful surrogate for mitigation and conservation planning under climate variability

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Ecological Processes 2024年第1期13卷 3-24页

作者： Pablo L.Peri juan Gaitán Matías Mastrangelo Marcelo Nosetto Pablo E.Villagra Ezequiel Balducci Martín Pinazo Roxana P.Eclesia Alejandra Von Wallis Sebastián Villarino Francisco Alaggia Marina González Polo Silvina Manrique Pablo A.Meglioli Julián Rodríguez-Souilla Martín Mónaco Jimena E.Chaves Ariel Medina Ignacio Gasparri Eugenio Alvarez Arnesi María Paula Barral Axel von Müller Norberto M.Pahr Josefina Uribe Echevarria Pedro Fernández Marina Morsucci Dardo López juan manuel cellini Leandro Alvarez Ignacio Barberis Hernán Colomb Ludmila La Manna Sebastián Barbaro Cecilia Blundo Ximena Sirimarco Laura Cavallero Gualberto Zalazar Guillermo Martínez Pastur Instituto Nacional de Tecnología Agropecuaria (INTA) Universidad Nacional de la Patagonia Austral (UNPA) Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Universidad Nacional de Luján Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Grupo de Estudio de Agroecosistemas y Paisajes Rurales (GEAP) Universidad Nacional de Mar del Plata Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET ) CCT San Luis Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Instituto Argentino de Nivología Glaciología y Ciencias Ambientales (IANIGLA) Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Universidad Nacional de Cuyo Instituto de Investigaciones en Biodiversidad y Medioambiente (INIBIOMA) Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Instituto de Investigaciones en Energía No Convencional CCT Salta-JujuyConsejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Laboratorio de Recursos Agroforestales Centro Austral de Investigaciones Científicas (CADIC) Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Dirección Nacional de Bosques Ministerio de Ambiente y Desarrollo Sostenible de la Nación Instituto de Ecología Regional Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET )Universidad Nacional de Tucumán Universidad Nacional de Rosario Instituto de Investigaciones en Ciencias Agrarias de Rosario Centro Científico Tecnológico CONICET Grupo de Estudio de Agroecosistemas y Paisajes Rurales (GEAP) Universidad Nacional de Mar del Plata Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Laboratorio de Investigaciones en Maderas (LIMAD) Universidad Nacional de La Plata (UNLP) Administración de Parques Nacionales (APN) Parque Nacional Los Alerces Centro de Estudios Ambientales Integrados (CEAI) Universidad Nacional de la Patagonia San Juan Bosco (UNPASJB) Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET )

Background The nationally determined contribution（NDC） presented by Argentina within the framework of the Paris Agreement is aligned with the decisions made in the context of the United Nations Framework Conven-tion on Climate Change（UNFCCC） on the reduction of emissions derived from deforestation and forest degradation, as well as forest carbon conservation（REDD+）. In addition, climate change constitutes one of the greatest threats to forest biodiversity and ecosystem services. However, the soil organic carbon（SOC） stocks of native forests have not been incorporated into the Forest Reference Emission Levels calculations and for conservation planning under cli-mate variability due to a lack of information. The objectives of this study were:（i） to model SOC stocks to 30 cm of native forests at a national scale using climatic, topographic and vegetation as predictor variables, and（ii） to relate SOC stocks with spatial–temporal remotely sensed indices to determine biodiversity conservation concerns due to threats from high inter-annual climate *** We used 1040 forest soil samples（0–30 cm） to generate spatially explicit estimates of SOC native forests in Argentina at a spatial resolution of approximately 200 m. We selected 52 potential predictive environmental covari-ates, which represent key factors for the spatial distribution of SOC. All covariate maps were uploaded to the Google Earth Engine cloud-based computing platform for subsequent modelling. To determine the biodiversity threats from high inter-annual climate variability, we employed the spatial–temporal satellite-derived indices based on Enhanced Vegetation Index（EVI） and land surface temperature（LST） images from Landsat *** SOC model（0–30 cm depth） prediction accounted for 69% of the variation of this soil property across the whole native forest coverage in Argentina. Total mean SOC stock reached 2.81 Pg C（2.71–2.84 Pg C with a probability of 90%） for a total area of 460,790 km2,

关键词： Soil organic carbon Biodiversity Native forest Climate change mitigation Modelling Resilience

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Models and observations of sunspot penumbrae

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Science China(Physics,Mechanics & Astronomy) 2009年第11期52卷 1670-1677页

作者： BORRERO juan manuel Max Planck Institut fr Sonnensystemforschung Max Planck Strasse 2 D 37191 Katlenburg-Lindau Germany

The mysteries of sunspot penumbrae have been under an intense scrutiny for the past 10 years. During this time, some models have been proposed and refuted, while the surviving ones had to be modified, adapted and evolved to explain the ever-increasing array of observational constraints. In this contribution I will review two of the present models, emphasizing their contributions to this field, but also pinpointing some of their inadequacies to explain a number of recent observations at very high spatial resolution (0.32 ). To help explaining these new observations I propose some modifications to each of those models. These modifications bring those two seemingly opposite models closer together into a general picture that agrees well with recent 3D magneto-hydrodynamic simulations.

关键词： sunspots magnetic fields spectropolarimetry magnetohydrodynamics

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Virtual Conductance Based Cascade Voltage Controller for VSCs in Islanded Operation Mode

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Journal of Modern Power Systems and Clean Energy 2022年第6期10卷 1704-1713页

作者： Francisco Jesús Matas-Díaz manuel Barragán-Villarejo juan Carlos Olives-Camps juan manuel Mauricio JoséMaría Maza-Ortega Department of Elec‐trical Engineering Universidad de SevillaSeville 41092Spain

Voltage source converters have become the main enabler for the integration of distributed energy resources in *** the case of islanded operation,these devices normally set the amplitude and frequency of the network voltage by means of a cascade controller composed of an outer voltage control loop and an inner current control *** strategies to compute the gains of both control loops have been proposed in the literature in order to obtain a fast and decoupled response of the voltages at the point of common *** paper proposes an alternative and simple methodology based on the introduction of a virtual conductance in the classic cascade *** strategy allows to design each control loop independently,obtaining a closed-loop response of a first-order *** this way,the gains of each control loop are easily derived from the parameters of the LC coupling filter and the desired closed-loop time ***,a state observer is included in the controller to estimate the inductor current of the LC filter in order to reduce the number of required measurements.A laboratory testbed is used to validate and compare the proposed *** experimental results demonstrate the effectiveness of the proposal both in steady-state and transient regimes.

关键词： Voltage source converter microgrid cascade controller virtual conductance

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Hot corrosion mechanism of yttria-stabilized zirconia powder in the presence of molten Na_(2)SO_(4)+V_(2)O_(5) salts

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Rare Metals 2021年第5期40卷 1307-1316页

作者： Jhonattan De la Roche juan manuel Alvarado-Orozco Alejandro Toro Tribology and Surfaces Group Universidad Nacional de ColombiaMedellin 050041Colombia Centro de Ingeniena y Desarrollo Industrial-CIDESI Queretaro 76125Mexico Consorcio de Manufactura Aditiva-CONMAD Queretaro 76125Mexico

The hot corrosion behavior of yttria-stabilized zirconia(YSZ)powder specimens exposed to Na_(2)SO_(4)/V_(2)O_(5) salts mixtures at high temperature was *** tests were carried out at 1000℃ for 10 h,the salt concentrations varied from 0.1 wt%to 1.00 wt%,and the Na_(2)SO_(4)/V_(2)O_(5) mass ratios were between 0.20 and 0.44 following a factorial design 22.X-ray diffraction(XRD)analyses of the tested samples showed with a confidence of95%that the mixture composed of 32 wt%Na_(2)SO_(4)+68 wt%V_(2)O_(5),and 1.00 wt% salt concentration led to high destabilization of the t’-YSZ phase and formation of YVO_(4) products.A second set of experiments were conducted to assess the influence of temperature on the hot corrosion response of the YSZ in the range between 490 and 1100℃.Thermogravimetric analysis(TGA)experiments and Rietveld adjustments of XRD patterns showed that the mass loss of the samples varied with testing temperature and also that the major destabilization of tetragonal phase occurred at 900℃.

关键词： Hot corrosion Molten salts Yttria-stabilized zirconia Thermal barrier coatings

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HEART RATE VARIABILITY DURING HIGH-INTENSITY EXERCISE

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Journal of Systems Science & Complexity 2013年第1期26卷 104-116页

作者： SARMIENTO Samuel GARCIA-MANSO juan manuel MARTIN-GONZALEZ juan manuel VA-AMONDE Diana CALDERóN Javier DA SILVA-GRIGOLETTO Marzo Edir Department of Physical Education University of Las Palmas de Gran Canaria Spain. Physics Department University of Las Palmas de Gran Canaria Spain. Department of Morphological Sciences School of Medicine University of Cdrdoba Spain. Physical Activity Sciences Faculty Polytechnic University of Madrid Spain. Andalusian Centre of Sports Medicine Cdrdoba Spain.

The aim of this paper is to describe and analyse the behaviour of heart rate variability(HRV)during constant-load,high-intensity exercise using a time frequency analysis(Wavelet Transform).Eleven elite cyclists took part in the study(age:18.6±3.0 years;VO_(2max):4.88±0.61 litres·min^(-1)).Initially,all subjects performed an incremental cycloergometer test to determine load power in a constant load-test(379.55±36.02 W;89.0%).HRV declined dramatically from the start of testing(p<0.05).The behaviour of power spectral density within the LF band mirrored that of total energy,recording a significant decrease from the outset LF peaks fell rapidly thereafter,remaining stable until the end of the ***-VHF fell sharply in the first 20 to 30 *** relative weighting(%) of HF-VHF was inverted with the onset of fatigue,[1.6%at the start,7.1(p<0.05) at the end of the first phase,and 43.1%(p<0.05) at the end of the test].HF-VHF_(peak) displayed three phases:a moderate initial increase,followed by a slight fall,thereafter increasing to the end of the *** LF/HF-VHF ratio increased at the start,later falling progressively until the end of the first phase and remaining around minimal values until the end of the test.

关键词： Cycling heart rate variability wavelet.

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BASKETBALL SCORING IN NBA GAMES:AN EXAMPLE OF COMPLEXITY

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Journal of Systems Science & Complexity 2013年第1期26卷 94-103页

作者： DE SA GUERRA Yves MARTíN GONZALEZ juan manuel SARMIENTO MONTESDEOCA Samuel RODRIGUEZ RUIZ David ARJONILLA LóPEZ Nieves GARCíA-MANSO juan manuel Departament of Phisical Education University of Las Palmas de Gran Canaria Departament of Physics University of Las Palmas de Gran Canaria

Scoring in a basketball game is a highly dynamic, non-linear process. NBA teams try to be more and more competitive each season. For instance, they incorporate into their rosters the best players in the world. This and other mechanisms concur to make the scoring process in NBA games exciting and rarely predictable. This paper is to study the behavior of timing and scoring in basketball gaines. The authors analyze all the games in five NBA regular seasons （2005-06, 2006-07, 2007-08, 2008-09, 2009-10）, for a total of 6150 games. Scoring does not behave uniformly; therefore, the authors also analyze the distributions of the differences in points in the basketball games. To further analyze the behavior of the tail of the distribution, the authors also carry out a semilog-plot and a log-log plot to verify whether this trend approaches a Poisson distribution or a PL. This paper reveals different areas of behavior related to the score, with specific instances of time that could be considered tipping points of the game. The presence of these critical points suggests that there are phase transitions where the dynamic scoring of the games varies significantly.

关键词： Complexity NBA non-linear Poisson power law.

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Hepatopulmonary syndrome: What we know and what we would like to know

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World Journal of Gastroenterology 2016年第25期22卷 5728-5741页

作者： Israel Grilo-Bensusan juan manuel Pascasio-Acevedo Digestive Diseases Department HAR écija APS Bajo Guadalquivir Unit for the Clinical Management of Digestive Diseases IBIS CIBERehd Virgen del Rocío University Hospital

Hepatopulmonary syndrome (HPS) is characterized by abnormalities in blood oxygenation caused by the presence of intrapulmonary vascular dilations (IPVD) in the context of liver disease, generally at a cirrhotic stage. Knowledge about the subject is still only partial. The majority of the information about the etiopathogenesis of HPS has been obtained through experiments on animals. Reported prevalence in patients who are candidates for a liver transplantation (LT) varies between 4% and 32%, with a predominance of mild or moderate cases. Although it is generally asymptomatic it does have an impact on their quality of life and survival. The diagnosis requires taking an arterial blood gas sample of a seated patient with alveolar-arterial oxygen gradient (AaO2) ≥ 15 mm Hg, or ≥ 20 mm Hg in those over 64 years of age. The IPVD are identified through a transthoracic contrast echocardiography or a macroaggregated albumin lung perfusion scan (99mTc-MAA). There is currently no effective medical treatment. LT has been shown to reverse the syndrome and improve survival rates, even in severe cases. Therefore the policy of prioritizing LT would appear to increase survival rates. This paper takes a critical and clinical look at the current understanding of HPS, as well as the controversies surrounding it and possible future research.

关键词： Hepatopulmonary syndrome Liver cirrhosis Liver transplantation Contrast echocardiography Macroaggregated albumin lung perfusion scan

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Oxidative effects of glyphosate on the lipophobic intracellular environment in the microalgae Chlorella vulgaris

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BIOCELL 2022年第3期46卷 795-802页

作者： juan manuel OSTERA SUSANA PUNTARULO GABRIELA MALANGA Fisicoquímica Facultad de Farmacia y BioquímicaUniversidad de Buenos AiresBuenos AiresCP 1113Argentina Instituto de Bioquímica y Medicina Molecular(IBIMOL) CONICET-Universidad de Buenos AiresBuenos AiresCP 1113Argentina

The studied hypothesis is that the herbicide glyphosate(GLY)can affect the oxidative balance in the hydrophobic intracellular medium in non-target Chlorella vulgaris *** GLY and RoundUp(RUP)supplementation,affected the growth profile.A significant 42%decrease in the cellular biomass in stationary(St)phase was observed in cultures supplemented with either 5μM of GLY or RUP,as compared to control *** treatment with 0.3μM of GLY generated non-significant effects on the oxidation rate of 2’,7’dichlorofluorescein diacetate(DCFH-DA),neither in exponential(Exp)nor in St phase of development,as compared to control ***,the treatment with either 5μM GLY or 0.3 and 5μM RUP lead to a significant decrease in the DCFH-DA oxidation rate,as compared to control *** lipid radical(LR●)generation rate,detected by Paramagnetic Resonance Spectroscopy(EPR),was significantly increased in the presence of RUP,in Lag and Exp phase of *** non-enzymatic antioxidants,α-Tocopherol(α-T)andβ-Carotene(β-C),are aimed to protect membranes against the damage produced by the radical *** content ofβ-C was not significantly affected,as compared to control cultures,by any of the treatments,in both growth phases of cellular *** content ofα-T was significantly decreased by the supplementation with either 0.3 or 5μM of RUP or 5μM *** LR●/α-T ratio,used as indicator of the oxidative balance in the hydrophobic cellular media,was significantly different between samples obtained from control and RUP-exposed microalgae in both,Exp and St phase of development,with either 0.3 or 5μM *** data presented here showed evidence that suggested that oxidative balance in the hydrophobic environment was affected by either GLY or RUP.

关键词： 2’,7’dichlorofluorescein diacetate oxidation rate Lipid soluble antioxidants Round up Redox balance

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Improved organs at risk segmentation based on modified U‐Net with self‐attention and consistency regularisation

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CAAI Transactions on Intelligence Technology 2024年第4期9卷 850-865页

作者： Maksym Manko Anton Popov juan manuel Gorriz Javier Ramirez Electronic Engineering Department Igor Sikorsky Kyiv Polytechnic InstituteKyivUkraine Department of Signal Theory Telematics and CommunicationsUniversity of GranadaGranadaSpain

Cancer is one of the leading causes of death in the world,with radiotherapy as one of the treatment *** planning starts with delineating the affected area from healthy organs,called organs at risk(OAR).A new approach to automatic OAR seg-mentation in the chest cavity in Computed Tomography(CT)images is *** proposed approach is based on the modified U‐Net architecture with the ResNet‐34 encoder,which is the baseline adopted in this *** new two‐branch CS‐SA U‐Net architecture is proposed,which consists of two parallel U‐Net models in which self‐attention blocks with cosine similarity as query‐key similarity function(CS‐SA)blocks are inserted between the encoder and decoder,which enabled the use of con-sistency *** proposed solution demonstrates state‐of‐the‐art performance for the problem of OAR segmentation in CT images on the publicly available SegTHOR benchmark dataset in terms of a Dice coefficient(oesophagus-0.8714,heart-0.9516,trachea-0.9286,aorta-0.9510)and Hausdorff distance(oesophagus-0.2541,heart-0.1514,trachea-0.1722,aorta-0.1114)and significantly outperforms the *** current approach is demonstrated to be viable for improving the quality of OAR segmentation for radiotherapy planning.

关键词： 3‐D computer vision deep learning deep neural networks image segmentation medical image processing object segmentation

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