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Environmental Factors that Affect Primary Plant Succession Trajectories on Lahars(Popocatépetl Volcano,Mexico)

Journal of Mountain Science 2015年第5期12卷 1254-1266页

作者： GARCIA-ROMERO Arturo ALANIS-ANAYA Rocío Marisol munoz-jimenez julio Departamento de Geografía Física Instituto de GeografíaUniversidad Nacional Autónoma de México.Circuitoexterior s/nCiudad Universitaria04510 MexicoDistrito FederalMexico Laboratorio de Análisis Geoespacial Instituto de GeografíaUniversidad Nacional Autónoma de México.Circuitoexterior s/nCiudad Universitaria04510 MexicoDistrito FederalMexico Departamento de A.G.R.y Geografía Física Facultad de Geografía e HistoriaUniversidad Complutense de Madrid.Calle Profesor Aranguren s/nCiudad Universitaria28040MadridSpain

The earliest stages of plant succession on severely disturbed sites usually follow highly unpredictable trajectories. However, in the Popocatépetl volcano area(50 km SE of Mexico City),the development of physiognomically distinct primary plant communities suggests the occurrence of various successional trajectories only 10 years after the onset of colonization of a temperate forest on lahars. To characterize plant communities and determine the environmental factors that drive the differences observed between plant communities and their successional trajectories, we monitored 64 circular sample plots(3.14 m2) from 2002 to 2011. We examined the plant communities' composition and structure in terms of their species richness and abundance, plant cover, and maximum stem height,and recorded 13 environmental factors related to the volcanic deposit characteristics, microclimate, soil,flow dynamics and gravitational processes. A cluster analysis of the species abundance data showed that,by 2011, six plant community types(CT's) had established, including grasslands, and open, dense and very dense shrub lands. As these communities developed over the same period of time and within the same overall ecosystem, then these plant community types were interpreted as different stages of the same successional trajectory. Two sequential main stages that drive regeneration were identified from this successional trajectory: a) the first four years are characterized by a steady increase in species richness and physiognomic development(plant size and coverage), mostly dominated by Baccharis conferta, Eupatorium glabratum and Senecio barbajohannis; b) from the sixth year onwards, a continued increase in the abundance of those same species led to the development of the dense shrubland *** in the availability of soil resources and disturbances linked to recent lahar flows were the main factors accounting for such differences.

关键词： Ecosystem regeneration Plantcolonization Primary succession Temperate forest Light exposure Elevation Soil Slope aspect

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Inconsistencies in four-dimensional Einstein-Gauss-Bonnet gravity

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Chinese Physics C 2021年第1期45卷 89-96页

作者： julio Arrechea Adria Delhom Alejandro jimenez-Cano Instituto de Astrofisica de Andalucia(IAA-CSIC) Glorieta de la AstronomiaGranadaSpain Departamento de Fisica Teorica and IFIC Centro Mixto Universidad de Valencia-CSIC.Universidad de ValenciaBuijassot-46100ValenciaSpain Departamento de Fisica Teorica y del Cosmos and CAFPE Universidad de Granada18071 GranadaSpain

We attempt to clarify several aspects concemi ng the recently presented four-dimensional Ein stein-Gauss-Bonnet *** argue that the limiting procedure outlined in[***.124,081301(2020)]generally involves ill-defined terms in the four dimensional field *** ways to circumvent this issue are discussed,alongside remarks regarding specific solutions of the *** prove that,although linear perturbations are well behaved around maximally symmetric backgrounds,the equations for second-order perturbations are illdefined even around a Minkowskia n *** on ally,we perform a detailed analysis of the spherically symmetric solutions and find that the central curvature singularity can be reached within a finite proper time.

关键词： alternative theories of gravity singularities Einstein・Gauss-Bonnet

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Prefoldins 3 and 5 Play an Essential Role in Arabidopsis Tolerance to Salt Stress

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Molecular Plant 2009年第3期2卷 526-534页

作者： Miguel A. Rodriguez-Milla julio Salinas Departamento de Biologfa de Plantas Centro de Investigaciones Biologicas-CSIC Ramiro de Maeztu 9 28040 Madrid Spain

During the last years, our understanding of the mechanisms that control plant response to salt stress has been steadily progressing. Pharmacological studies have allowed the suggestion that the cytoskeleton may be involved in regulating such a response. Nevertheless, genetic evidence establishing that the cytoskeleton has a role in plant tolerance to salt stress has not been reported yet. Here, we have characterized Arabidopsis T-DNA mutants for genes encoding proteins orthologous to prefoldin （PFD） subunits 3 and 5 from yeast and mammals. In these organisms, PFD subunits, also known as Genes Involved in Microtubule biogenesis （GIM）, form a heterohexameric PFD complex implicated in tubulin and actin folding. We show that, indeed, PFD3 and PFD5 can substitute for the loss of their yeast orthologs, as they are able to complement yeast gim2Δ and gim5Δ mutants, respectively. Our results indicate that pfd3 and pfd5 mutants have reduced levels of α- and β-tubulin compared to the wild-type plants when growing under both control and salt-stress conditions. In addition, pfd3 and pfd5 mutants display alterations in their developmental patterns and microtubule organization, and, more importantly, are hypersensitive to high concentrations of NaCl but not of LiCl or mannitol. These results demonstrate that the cytoskeleton plays an essential role in plant tolerance to salt stress.

关键词： Prefoldins cytoskeleton tubulin actin microtubule salt tolerance Arabidopsis

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Accuracy of endoscopic ultrasound-guided tissue acquisition in the evaluation of lymph nodes enlargement in the absence of on-site pathologist

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World Journal of Gastroenterology 2017年第31期23卷 5755-5763页

作者： Yung Ka Chin julio Iglesias-Garcia Daniel de la Iglesia Jose Larino-Noia Ihab Abdulkader-Nallib Hector Lázare Susana Rebolledo Olmedo J Enrique Dominguez-munoz Department of Gastroenterology and Hepatology University Hospital of Santiago de Compostela Health Research Institute of Santiago de Compostela (IDIS) University Hospital of Santiago de Compostela Department of Pathology University Hospital of Santiago de Compostela

To evaluate factors that influence the diagnostic accuracy of endoscopic ultrasound (EUS)-guided tissue acquisition for lymph node enlargement in the absence of an on-site pathologist. METHODSA retrospective analysis of patients who underwent EUS-guided tissue acquisition for the pathological diagnosis of lymph node enlargement between April 2012 and June 2015 is reported. Tissue acquisition was performed with both cytology and biopsy needles of different calibers. The variables evaluated were lymph node location and size, number of passes and type of needle used. Final diagnosis was based on surgical histopathology or, in non-operated cases, on EUS-guided tissue acquisition and imaging assessment with a minimum clinical follow-up of 6 mo. RESULTSDuring the study period, 168 lymph nodes with a median size of 20.3 mm (range 12.5-27) were sampled from 152 patients. Ninety lymph nodes (53.6%) were located at mediastinum, and 105 (62.5%) were acquired with biopsy needles. The final diagnosis was benign/reactive origin in 87 cases (51.8%), malignant in 65 cases (38.7%), and lymphoma in 16 cases (9.5%). The sensitivity, specificity, positive predictive value and negative predictive value for the detection of malignancy were 74.1%, 100%, 100% and 80.6%, respectively. The overall accuracy was 87.5% (95%CI: 81.7-91.7). No variables were independently associated with a correct final diagnosis according to the multivariate analysis. CONCLUSIONEUS-guided tissue acquisition is a highly accurate technique for assessing lymph node enlargement. None of the variables evaluated were associated with diagnostic accuracy.

关键词： Lymph node Endoscopic ultrasound Fine-needle aspiration Fine-needle biopsy Accuracy

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Linear OPF-based Robust Dynamic Operating Envelopes with Uncertainties in Unbalanced Distribution Networks

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Journal of Modern Power Systems and Clean Energy 2024年第4期12卷 1320-1326页

作者： Bin Liu julio H.Braslavsky Nariman Mahdavi Energy Centre Commonwealth Scientific and Industrial Research Organisation(CSIRO)Newcastle 2300Australia the Network Planning Division TransgridSydney 2000Australia the Energy Systems Program Energy CentreCommonwealth Scientific and Industrial Research Organisation(CSIRO)Newcastle 2300Australia

Dynamic operating envelopes(DOEs),as key enablers to facilitate distributed energy resource(DER)integration,have attracted increasing attention in the past ***,uncertainties,which may come from load forecasting errors or inaccurate network parameters,have been rarely discussed in DOE calculation,leading to compromised quality of the hosting capacity allocation *** letter studies how to calculate DOEs that are immune to such uncertainties based on a linearised unbalanced three-phase optimal power flow(UTOPF)*** uncertain parameters constrained by norm balls,formulations for calculating robust DOEs(RDOEs)are presented along with discussions on their *** cases,including a 2-bus illustrative network and a representative Australian network,are tested to demonstrate the effectiveness and efficiency of the proposed approach.

关键词： Distributed energy resource(DER) dynamic operating envelope(DOE) feasible region robust optimisation uncertainty modelling unbalanced optimal power flow

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SIMPLE COMPUTING OF THE CUSTOMER LIFETIME VALUE:A FIXED LOCAL-OPTIMAL POLICY APPROACH

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Journal of Systems Science and Systems Engineering 2014年第4期23卷 439-459页

作者： julio B.Clempner Alexander S.Poznyak Center for Economics Management and Social Research Department of Control Automatics Center for Research and Advanced Studies

In this paper,we present a new method for finding a fixed local-optimal policy for computing the customer lifetime *** method is developed for a class of ergodic controllable finite Markov *** propose an approach based on a non-converging state-value function that fluctuates（increases and decreases） between states of the dynamic *** prove that it is possible to represent that function in a recursive format using a one-step-ahead fixed-optimal ***,we provide an analytical formula for the numerical realization of the fixed local-optimal *** also present a second approach based on linear programming,to solve the same problem,that implement the c-variable method for making the problem computationally *** the end,we show that these two approaches are related：after a finite number of iterations our proposed approach converges to same result as the linear programming *** also present a non-traditional approach for ergodicity *** validity of the proposed methods is successfully demonstrated theoretically and,by simulated credit-card marketing experiments computing the customer lifetime value for both an optimization and a game theory approach.

关键词： Customer lifetime value optimization optimal policy method linear programming ergodic controllable Markov chains asynchronous games

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Encroachment drives facilitation at alpine shrublines

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Forest Ecosystems 2024年第1期11卷 62-72页

作者： Yafeng Wang Eryuan Liang J.julio Camarero College of Ecology and Environment Nanjing Forestry UniversityNanjing210037China State Key Laboratory of Tibetan Plateau Earth System Environment and Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing100101China Instituto Pirenaico de Ecología(IPE-CSIC) Zaragoza50080Spain

Ongoing encroachment is driving recent alpine shrubline dynamics globally,but the role of shrub-shrub interactions in shaping shrublines and their relationships with stem density changes remain poorly ***,the size and age of shrubs from 26 Salix shrubline populations along a 900-km latitudinal gradient(30°-38°N)were measured and mapped across the eastern Tibetan *** pattern analyses were used to quantify the spatial distribution patterns of juveniles and adults,and to assess spatial associations between *** intensity of univariate and bivariate spatial patterns was related to biotic and abiotic *** mark correlation functions with a quantitative mark(shrub height,basal stem diameter,crown width)were also employed to investigate the spatial relationships between shrub traits of juveniles and *** equation models were used to explore the relationships among conspecific interactions,patterns,shrub traits and recruitment dynamics under climate *** shrublines showed clustered patterns,suggesting the existence of conspecific *** patterns of juveniles and conspecific interactions(potentially facilitation)tended to intensify with increasing soil moisture *** warming before 2010 triggered positive effects on population interactions and spatial patterns via increased shrub ***,summer warming after2010 triggered negative effects on interactions through reduced shrub ***,shrub recruitment shifts under rapid climate change could impact spatial patterns,alter conspecific interactions and modify the direction and degree of shrublines responses to *** changes would have profound implications for the stability of alpine woody ecosystems.

关键词： Alpine shrubline Positive interactions Facilitation Spatial clustering Point pattern analyses

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Interpenetrating polymers supported on microporous polypropylene membranes for the transport of chromium ions

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Chinese Journal of Chemical Engineering 2017年第7期25卷 938-946页

作者： Yesid Tapiero julio Sánchez BernabéL.Rivas Polymer Department Faculty of ChemistryUniversity of ConcepdonCasilla 160-C ConcepcionChile

Modifying polypropylene membranes with interpenetrating polymer networks(IPNs) through the incorporation of poly(glycidyl methacrylate-N-methyl-D-glucamine)(P(GMA-NMG)) was performed by in situ synthesis via radical polymerization. The surface of the polypropylene membrane was activated by hydrophilic grafted polyelectrolyte, and then, pressure injection was used for the impregnation of the reactive solution in the *** types of pore-filled membranes were synthesized, chelating interpenetrating homopolymer networks of P(GMA-NMG), and chelating-ion exchange interpenetrating polymer networks(e.g., P(GMA-NMG)/P(AA),P(GMA-NMG)/P(AMPSA), and P(GMA-NMG)/P(Cl VBTA)). After their synthesis, the modified polypropylene membranes were characterized using techniques such as the electrokinetic potential, SEM, FT-IR, and Donnan dialysis to corroborate the chromium ion transport. The P(GMA-NMG) and complex network membranes exhibited a hydrophilic character with a water-uptake capacity between 20% and 35% and a percentage of modification between 4.0% and 7.0% in comparison with the behavior of the unmodified polypropylene *** chromium ions were efficiently transported from the food chamber at p H 9.0 when the 65.2%MTA1 P(Cl VBTA) homopolymer IPN membrane and 48.5% MTAG P(GMA-NMG)/P(Cl VBTA) IPN membrane were used. Similarly, hexavalent chromium ions were removed from the food chamber at pH 3.0 when MTAG(63.30%) and MTA1(35.68%) were used in 1 mol·L^(-1)Na Cl solution as the extraction reagent.

关键词： Polypropylene N-methyI-D-glucamine Ion exchange Donnan dialysis Interpenetrating polymer networks Chromium

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CBFs at the Crossroads of Plant Hormone Signaling in Cold Stress Response

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Molecular Plant 2017年第4期10卷 542-544页

作者： Javier Barrero-Gil julio Salinas Departamento de Biología Medioambiental Centro de Investigaciones Biológicas-CSIC Ramiro de Maeztu 9 28040 Madrid Spain

Brassinosteroids （BRs） are steroid plant hormones with important roles in plant growth and development through the regulation of processes such as cell division and expansion. In addition to their role as growth promoters, BRs can also protect plants from a va- riety of abiotic stresses, including drought, salt, heat, and cold stress. Nevertheless, the molecular determinants underlying this protective effect remain largely uncharacterized.

关键词： CBFs Crossroads Plant Hormone Signaling

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Different xylogenesis responses to atmospheric water demand contribute to species coexistence in a mixed pine–oak forest

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Journal of Forestry Research 2023年第1期34卷 51-62页

作者： Marín Pompa-García J.julio Camarero Michele Colangelo Facultad de Ciencias Forestales y Ambientales de la Universidad Juárez del Estado de Durango Río Papaloapan y Blvd.Durango S/N Col.Valle del SurDurangoMéxico Instituto Pirenaico de Ecología(IPE-CSIC) Avda.Montanna 1005ZaragozaSpain School of Agricultural ForestFood and Environmental SciencesUniv.BasilicataPotenzaItaly

Seasonal patterns of wood formation(xylogenesis)remain understudied in mixed pine-oak forests despite their contribution to tree coexistence through temporal niche *** was assessed in three pine species(Pinus cembroides,Pinus leiophylla,Pinus engelmannii)and one oak(Quercus grisea)coexisting in a semi-arid Mexican *** main xylogenesis phases(production of cambium cells,radial enlargement,cell-wall thickening and maturation)were related to climate data considering 5-15-day temporal *** pines,cambium activity maximized from mid-March to April as temperature and evaporation increased,whereas cell radial enlargement peaked from April to May and was constrained by high evaporation and low ***-wall thickening peaked from June to July and in August-September as maximum temperature and vapour pressure deficit(VPD)*** of earlywood and latewood tracheids occurred in May-June and June-July,enhanced by high minimum temperatures and VPD in *** and *** oak,cambial onset started in March,constrained by high minimum temperatures,and vessel radial enlargement and radial increment maximized in April as temperatures and evaporation increased,whereas early wood vessels matured from May to June as VPD ***,15-day wet conditions enhanced cell radial enlargement in *** and ***,whereas early-summer high 15-day temperature and VPD drove cell-wall thickening in *** night conditions and high evaporation rates during spring and summer enhanced *** earlier growth peak in oak and a higher responsiveness to spring-summer water demand in pines contributed to their coexistence.

关键词： Bimodal growth Drought Vapour pressure deficit Wood formation Xylem phenology

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