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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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Unveiling the controversial mechanism of reversible Na storage in Tio2 nanotube arrays： Amorphous versus anatase Tio2

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Nano Research 2017年第8期10卷 2891-2903页

作者： Federico bella Ana b. Munoz-garcia Giuseppina Meligrana Andrea Lamberti Matteo Destro Michele Pavone Claudio Gerbaldi GAME Lab CHENERGY Group Department of Applied Science and Technology - DISAT Politecnico di Torino Corso Duca degli Abruzzi 24 10129 Torino Italy Department of Chemical Sciences University of Naples Fedefico II Via Cintia 21 University Campus of Monte Sant'Angelo 80126 Napoli Italy MPMNT Group Department of Applied Science and Technology - DISAT Politecnico di Torino Corso Duca degli Abruzzi 24 10129 Torino Italy LITHoPS S.r.l. Strada del Portone 61 10137 Torino Italy

Due to their inherent safety, low cost, and structural stability, Tio2 nanostructures represent a suitable choice as anode materials in sodiumion batteries. In the recent years, various hypotheses have been proposed regarding the actual mechanism of the reversible insertion of sodium ions in the Tio2 structure, and previous reports are often controversial in this respect. Interestingly, when tested as binder- and conducting additive-free electrodes in laboratory-scale sodium cells, amorphous and crystalline （anatase） Tio2 nanotubular arrays obtained by simple anodic oxidation exhibit peculiar and intrinsically different electrochemical responses. In particular, after the initial electrochemical activation, anatase Tio2 shows excellent rate capability and very stable long-term cycling performance with larger specific capacities, and thus a clearly superior response compared with the amorphous counterpart. To obtain deeper insight, the present materials are thoroughly characterized by scanning electron microscopy and ex situ X-ray diffraction, and the insertion of sodium ions in the Tio2 bulk phases is systematically modeled by density functional theory calculations. The present results may contribute to the development of more systematic screening approaches to identify suitable active materials for highly efficient sodium-based energy storage systems.

关键词： sodium battery Tio2 nanotube array anode modeling insertion mechanism

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Wettability of silicon carbide ceramic by Al_2o_3/Dy_2o_3 and Al_2o_3/Yb_2o_3 systems

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Journal of Rare Earths 2013年第6期31卷 634-638页

作者： J.A.da Silva b.M.Moreschi G.C.R.garcia S.Ribeiro Department of Materials Engineering (DEMAR) Engineering School of Lorena (EEL)Pólo Urbo IndustrialGleba AI6CP 11612608-970LorenaSPBrazil

Wettability is an important phenomenon in the liquid phase sintering of silicon carbide （SiC） ceramics. This work involved a study of the wetting of SiC ceramics by two oxide systems, Al2o3 /Dy2o3 and Al2o3 /Yb2o3, which have so far not been studied for application in the sintering of SiC ceramics. Five mixtures of each system were prepared, with different compositions close to their respective eutectic ones. Samples of the mixtures were pressed into cylindrical specimens, which were placed on a SiC plate and subjected to temperatures above their melting points using a graphite resistance furnace. The behavior of the melted mixtures on the SiC plate was observed by means of an imaging system using a CCD camera and the sessile drop method was employed to determine the contact angle, the parameter that measures the degree of wettability. The results of variation in the contact angle as a function of temperature were plotted in graphic form which showed that the curves displayed a fast decline and good spreading. All the samples of the two systems presented final contact angles of 40o to 10o indicating their good wetting on SiC in the argon atmosphere. The melted/solidified area and interface between SiC and melted/solidified phase were evaluated by scanning electron microscopy （SEM） and their crystalline phases were identified by X-ray diffraction （DRX）. The DRX analysis showed that Al2o3 and RE2o3 reacted and formed the Dy3Al5o12 （DyAg） and Yb3Al5o12 （YbAg） phases. The results indicated that the two systems had a promising potential as additives for the sintering of SiC ceramics.

关键词： liquid-phase sintering silicon carbide rare earth oxide wettability contact angle

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brazilian payment for environmental services programs emphasize water-related services

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International Soil and Water Conservation Research 2023年第2期11卷 276-289页

作者： Ingrid Mamedes Angélica Guerra Dulce b.b.Rodrigues Letícia Couto garcia Raquel de Faria Godoi Paulo Tarso S.oliveira Faculty of Engineering Architecture and Urbanism and GeographyFederal University of Mato Grosso do SulMS79070-900Brazil Programa de Pós-Graduaçāo em Ecologia e Conservaaçāo Universidade Federal de Mato Grosso do SulCampo GrandeBrazil Laboratorio de Ecologia da Intervenaçāo-LEl Instituto de BiociênciasUniversidade Federal de Mato Grosso do SulCampo GrandeBrazil Department of Hydraulics and Sanitary Engineering Sao Carlos School of EngineeringUniversity of Sao PauloSao CarlosSPBrazil

based on"user pays"and"provider gets"principles,the Payment for Environmental Services(PES)consists of providing economic incentives or compensation for land users who adopt activities that promote ecosystem *** PES initiatives have grown rapidly in brazil over the last few decades,however,studies that address the panorama of these programs in the country are still scarce,regional,or ***,we investigate the PES overview in brazil through interviews and an extensive literature *** found in total 80 PES programs implemented in brazil,of which 14 were *** pro-grams are poorly distributed across the country,mostly concentrated in the Atlantic Forest(56.25%)and Savanna(36.25%)biomes,in Southeastern *** majority of programs primarily prioritize improving water quality and ***,reforestation,protection of native vegetation,and soil and water conservation are their main proposed *** positive impacts of brazil's PES experi-ences are evident;while the lack of transparency and monitoring,and poor spatial and financial dis-tribution are still major *** conclude that if correctly implemented,PES schemes offer a path to reconcile environmental conservation with agricultural production in brazil.

关键词： Conservation funding Ecological restoration Environmental compliance Public policy Soil and water conservation

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LDH conversion films for active protection of AZ31 Mg alloy

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Journal of Magnesium and Alloys 2023年第1期11卷 201-216页

作者： b.Pillado b.Mingo R.del olmo E.Matykina A.M.Kooijman Y.Gonzalez−garcia R.Arrabal M.Mohedano Departamento de Ingeniería Química y de Materiales Facultad de Ciencias QuímicasUniversidad ComplutenseMadrid 28040Spain Department of Materials University of ManchesterOxford RoadManchester M139PLUK Institute of optoelectronics Military University of Technology2 Kaliskiego Str.Warsaw 00-908Poland Materials Science and Engineering Department Delft University of TechnologyMekelweg 2Delft 2628 CDthe Netherlands

Zinc aluminium(Zn-Al)and lithium aluminium(Li-Al)–layered double hydroxides(LDH)coatings with incorporated inhibitors(Li-,Mo-and W-based)were successfully synthesized on AZ31 Mg ***-Al LDH W and Li-Al LDH Li showed the highest corrosion resistance and were selected for further *** cross-section examination revealed a bi-layer structure composed of an outer part with loose flakes and a denser inner ***,FTIR,and XPS analysis confirmed the incorporation of the ***-treatments with corrosion inhibitors containing solutions resulted in the selective dissolution of the most external layer of the LDH coating,reducing the surface roughness,hydrophilicity and paint adhesion of the *** corrosion properties were confirmed by SVET evaluation for the Zn-Al LDH W *** proposed active corrosion mechanism involves the ion-exchange of aggressive Cl-ions,deposition of hydroxides and competitive adsorption of W-rich corrosion inhibitors.

关键词： AZ31 Magnesium Layered double hydroxides Corrosion inhibitors Active corrosion protection

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Using the polymerase chain reaction coupled with denaturing gradient gel electrophoresis to investigate the association between bacterial translocation and systemic inflammatory response syndrome in predicted acute severe pancreatitis

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World Journal of Gastroenterology 2005年第45期11卷 7142-7147页

作者： Callum b Pearce Vitaly Zinkevich Iwona beech Viera Funjika Ana garcia Ruiz Afraa Aladawi Hamish D Duncan Queen Alexandra Hospital Microbiology Research Laboratory

AIM: To investigate the use of PCR and DGGE to investigate the association between bacterial translocation and systemic inflammatory response syndrome in predicted severe ***: Patients with biochemical and clinical evidence of acute pancreatitis and an APACHE Ⅱ score ≥8 were enrolled. PCR and DGGE were employed to detect bacterial translocation in blood samples collected on d1,3, and 8 after the admission. Standard microbial blood cultures were taken when there was clinical evidence of sepsis or when felt to be clinically indicated by the supervising ***: Six patients were included. of all the patients investigated, only one developed septic complications;the others had uneventful illness. bacteria were detected using PCR in 4 of the 17 collected blood samples. The patient with sepsis was PCR-positive in two samples (taken on d 1 and 3), despite three negative blood cultures. Using DGGE and specific primers, the bacteria in all blood specimens which tested positive for the presence of bacterial DNA were identified as E ***: our study confirmed thatunlike traditional microbiological techniques, PCR can detect the presence of bacteria in the blood of patients with severe AP. Therefore, this latter method in conjunction with DGGE is potentially an extremely useful tool in predicting septic morbidity and evaluating patients with the disease. Further research using increased numbers of patients, in particular those patients with necrosis and sepsis, is required to assess the reliability of PCR and DGGE in the rapid diagnosis of infection in AP.

关键词： Polymerase chain reaction Acutepancreatitis bacterial translocation

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Improving wood volume predictions in dry tropical forest in the semi-arid brazil

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Journal of Arid Land 2020年第6期12卷 1046-1055页

作者： Robson b de LIMA Patrícia A b bARRETo-garcia Alessandro de PAULA Jhuly E S PEREIRA Flávia F de CARVALHo Silvio H M GoMES Department of Forest Engineering State University of AmapáMacapá68900070Brazil Department of Forest Science State University of Southwest BahiaVitória da Conquista 45083900Brazil Universidade Federal de Lavras Lavras 37200900Brazil Universidade de São Paulo Piracicaba 13418900Brazil

The volumetric variability of dry tropical forests in brazil and the scarcity of studies on the subject show the need for the development of techniques that make it possible to obtain adequate and accurate wood volume *** this study,we analyzed a database of thinning trees from a forest management plan in the Contendas de SincoráNational Forest,southwestern bahia State,*** data set included a total of 300 trees with a trunk diameter ranging from 5 to 52 ***,validation and statistical selection of four volumetric models were *** to the difference in height values for the same diameter and the low correlation between both variables,we do not suggest models which only use the diameter at breast height(DbH)variable as a predictor because they accommodate the largest estimation *** comparing the best single entry model(Hohenald-Krenn)with the Spurr model(best fit model),it is noted that the exclusion of height as a predictor causes the values of 136.44 and 0.93 for Akaike information criterion(AIC)and adjusted determination coefficient(R2 adj),which are poorer than the second best model(Schumacher-Hall).Regarding the minimum sample size,errors in estimation(root mean square error(RMSE)and bias)of the best model decrease as the sample size increases,especially when a larger number of trees with DbH≥15.0 cm are randomly *** sampling by diameter class produces smaller volume prediction errors than random sampling,especially when considering all *** summary,the Spurr and Schumacher-Hall models perform *** models suggest that the total variance explained in the estimates is not less than 95%,producing reliable forecasts of the total volume with *** estimates indicate that the bias around the average is not greater than 7%.our results support the decision to use regression methods to build models and estimate their parameters,seeking stratification strategies in diameter classes for the sample trees.

关键词： volume modeling minimal sample size Caatinga Spurr model forest management

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Systemic analysis of metabolome reconfiguration in Arabidopsis after abiotic stressors uncovers metabolites that modulate defense against pathogens

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Plant Communications 2024年第1期5卷 55-68页

作者： Antoni garcia-Molina Victoria Pastor Centre for Research in Agricultural Genomics(CRAG)CSIC-IRTA-UAb-Ub C/Vall MorontaEdifici CRAG08193 Bellaterra(Cerdanyola del Valles)BarcelonaSpain Department of biology Biochemistryand Natural SciencesSchool of Technology and Experimental SciencesUniversitat Jaume I12006 Castellode la PlanaSpain

Understanding plant immune responses is complex because of the high interdependence among biological processes in homeostatic ***,the integration of environmental cues causes network rewiring that interferes with defense ***,plants retain molecular signatures configured under abiotic stress periods to rapidly respond to recurrent stress,and these can alter *** changes imposed by abiotic stressors are persistent,although their impact on defense remains to be *** this study,we profiled metabolomes of Arabidopsis plants under several abiotic stress treatments applied individually or simultaneously to capture temporal trajectories in metabolite composition during adverse conditions and *** systemic analysis was performed to address the relevance of me-tabolome changes and extract central features to be tested in *** results demonstrate irreversibility in major fractions of metabolome changes as a general pattern in response to abiotic stress ***-tionalanalysisofmetabolomesandco-abundancenetworkspoints toconvergence inthereconfigurationof organic acid and secondary metabolite *** mutant lines for components related to these metabolic pathways showed altered defense capacities against different ***,our data suggest that sustained metabolome changes configured in adverse environments can act as mod-ulators of immune responses and provide evidence for a new layer of regulation in plant defense.

关键词： abiotic stress Arabidopsis biotic stress combinatorial stress metabolomics systems biology

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How small could a pup sound？ The physical bases of signaling body size in harbor seals

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Current Zoology 2017年第4期63卷 457-465页

作者： Andrea RAVIGNANI Stephanie GRoSS Maxime garcia Ana RUbIo-garcia bart DE boER Veterinary & Research Department Sealcentre Pieterburen Hoofdstraat 94a Pieterburen AG 9968 The Netherlands Artificial Intelligence Laboratory Vrije Universiteit Brussel Pleinlaan 2 Brussels 1050 Belgium Language and Cognition Department Max Planck Institute for Psycholinguistics Wundtlaan 1 Nijmegen XD 6525 The Netherlands Institute for Terrestrial and Aquatic Wildlife Research University of Veterinary Medicine Hannover Foundation Werftstrasse 6 Buesum 25761 Germany ENES Lab/Neuro-PSI CNRS UMR9197 University of Lyon/Saint Etienne 23 rue Paul Michelon 42023 Saint-Etienne cedex 2 France

Vocal communication is a crucial aspect of animal behavior. The mechanism which most mam- mals use to vocalize relies on three anatomical components. First, air overpressure is generated in- side the lower vocal tract. Second, as the airstream goes through the glottis, sound is produced via vocal fold vibration. Third, this sound is further filtered by the geometry and length of the upper vocal tract. Evidence from mammalian anatomy and bioacoustics suggests that some of these three components may covary with an animal＇s body size. The framework provided by acoustic al- Iometry suggests that, because vocal tract length （VTL） is more strongly constrained by the growth of the body than vocal fold length （VFL）, VTL generates more reliable acoustic cues to an animal＇s size. This hypothesis is often tested acoustically but rarely anatomically, especially in pinnipeds. Here, we test the anatomical bases of the acoustic allometry hypothesis in harbor seal pups Phoca vitulina. We dissected and measured vocal tract, vocal folds, and other anatomical features of 15 harbor seals post-mortem. We found that, while VTL correlates with body size, VFL does not. This suggests that, while body growth puts anatomical constraints on how vocalizations are filtered by harbor seals＇ vocal tract, no such constraints appear to exist on vocal folds, at least during puppy- hood. It is particularly interesting to find anatomical constraints on harbor seals＇ vocal tracts, the same anatomical region partially enabling pups to produce individually distinctive vocalizations.

关键词： acoustic allometry honest signaling larynx pinniped vocal tract.

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Prospects for sociogenomics in avian cooperative breeding and parental care

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Current Zoology 2020年第3期66卷 293-306页

作者： Flavia TERMIGNoNI-garcia Matthew I.M.LoUDER Christopher N.bALAKRISHNAN Lauren o’CoNNELL Scott V.EDWARDS Department of organismic and Evolutionary biology Harvard UniversityCambridgeMA 02138USA Museum of Comparative Zoology Harvard UniversityCambridgeMA 02138USA International Research Center for Neurointelligence The University of TokyoHongoBunkyo-kuTokyo 113-0033Japan Department of biology East Carolina UniversityGreenvilleNC 27858USA Department of biology Stanford UniversityStanfordCA 94305USA

For the last 40 years,the study of cooperative breeding(Cb)in birds has proceeded primarily in the context of discovering the ecological,geographical,and behavioral drivers of *** advent of molecular tools in the early 1990s assisted in clarifying the relatedness of helpers to those helped,in some cases,confirming predictions of kin selection *** for genome-wide analysis of sequence variation,gene expression,and epigenetics promise to add new dimensions to our understanding of avian Cb,primarily in the area of molecular and developmental correlates of delayed breeding and dispersal,as well as the ontogeny of achieving parental status in ***,we outline key ways in which modern-omics approaches,in particular genome sequencing,transcriptomics,and epigenetic profiling such as ATAC-seq,can be used to add a new level of ana-lysis of avian *** on recent and ongoing studies of avian social behavior and sociogenom-ics,we review how high-throughput sequencing of a focal species or clade can provide a robust foundation for downstream,context-dependent destructive and non-destructive sampling of spe-cific tissues or physiological states in the field for analysis of gene expression and epigenetics.-omics approaches have the potential to inform not only studies of the diversification of Cb over evolutionary time,but real-time analyses of behavioral interactions in the field or *** of birds represents a new branch in the network of methods used to study Cb,and can help clarify ways in which the different levels of analysis of Cb ultimately interact in novel and unexpected ways.

关键词： ATAC-seq behavior convergent evolution epigenetics neurobiology phylogeny

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