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Re-folded structure of syn-orogenic granitoids(Padrón dome, nW Iberia):Assessing rheological evolution of cooling continental crust in a collisional setting

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Geoscience Frontiers 2019年第2期10卷 651-669页

作者： Rubén Díez Fernández Francisco J.Rubio Pascual Luis Miguel Martín Parra departamento de Geodinámica Estratigrafía y PaleontologíaFacultad de Ciencias GeológicasUniversidad Complutense de Madrid instituto Geológico y Minero de Espana

This contribution discusses about the rheological, kinematic and dynamic frameworks necessary to produce recumbent and upright folds from syn-orogenic granitic massifs that were formed during an early stage of magma genesis related to the onset of a migmatitic dome. syn-kinematic granitoids occurring within the high-grade infrastructure of the Padron migmatitic dome(nW Iberia) are deformed into largescale recumbent folds(D_2) that are later affected by upright folds(D_3). Petrostructural analysis of a selected area of this dome reveals that after a period of crustal thickening(D_1), nnW-directed extensional flow gave way to recumbent folds and penetrative axial plane foliation(s_2). superimposed subhorizontal compression resulted in upright folds(D_3). A closer view into the dynamics of the dome allows exploring the factors that may condition the nucleation of folds with contrasting geometries during progressive deformation of molten continental crust. The formation of folds affecting syn-kinematic granitoids suggests a cooling metamorphic path in migmatitic domes. Active and passive folding mechanisms require a crystallizing(cooling) magma to nucleate folds. A more competent metamorphic host inhibits fold nucleation from much less competent magmas. As it crystallizes, magma becomes more rigid(competent),and approaches viscosity values of its host. Passive folding is favored when no significant competence contrast exists between magma and host, so this folding mechanism is more likely shortly after magma genesis and emplacement. In such conditions, and under dominant subhorizontal flow accompanied by flattening(D_2),passive folding would produce isoclinal recumbent geometries. Further magma cooling introduces a shift into the rheological behavior of partially molten crust. Thereon, crystallizing magma bodies would represent significant competence contrasts relative to their host. At this point, buckling is a more likely folding mechanism, and more regular, buckle fo

关键词： Recumbent folds Migmatitic domes Partial melting Crustal-derived granitoids Orogenic collapse Variscan orogen

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Assessing above-ground biomass-functional diversity relationships in temperate forests in northern Mexico

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Forest Ecosystems 2021年第1期8卷 95-108页

作者： Benedicto Vargas-Larreta Jorge Omar López-Martínez Edgar J.González JoséJavier Corral-Rivas Francisco Javier Hernández Tecnológico nacional de México/instituto Tecnológico de El salto 34942 El SaltoDurangoMexico Cátedras CONACYT1582Av.Insurgentes SurCiudad de MéxicoMexico El Colegio de la Frontera sur 77014ChetumalQuintana RooMexico departamento de Ecología y Recursos naturales Facultad de CienciasUniversidad Nacional Autónoma de MéxicoCiudad de MéxicoMexico Facultad de ciencias Forestales Universidad Juárez del Estado de DurangoRío Papaloapan y Blvd.Durango s/nCol.Valle del Sur34120 DurangoMexico

Background:studies on the relationship between biodiversity and ecosystem productivity have suggested that species richness and functional diversity are the main drivers of ecosystem *** patterns on this relationship have been found,including positive,unimodal,negative,and neutral trends,keeping the issue *** this study,taxonomic diversity and functional diversity as drivers of above-ground biomass(AGB)were compared,and the mechanisms that influence biomass production were investigated by testing the complementarity and the mass-ratio ***:Using data from 414 permanent sample plots,covering 23%of temperate forest in the sierra Madre Oriental(México),we estimated the above-gound biomass(AGB),taxonomic and functional diversity indices,as well as community weighted mean values(CWM)for three functional traits(maximum height,leaf size and wood density)for trees≥7.5 cm DBH,in managed and unmanaged *** compare taxonomic diversity differences between managed and unmanaged stands we carried out a rarefaction ***,we evaluated the relationship between AGB and taxonomic and functional diversity metrics,as well as CWM traits throught spatial autoregressive ***:We found a hump-shaped relationship between AGB and species richness in managed and unmanaged *** of maximum height was the most important predictor of AGB in both stands,which suggested that the mechanism underlaying the AGB-diversity relationship is the dominance of some highly productive species,supporting the mass-ratio ***-ground biomass was significantly correlated with three of the five functional diversity metrics,CWM maximum height and species *** results show the importance of taking into account spatial autocorrelation in the construction of predictive models to avoid spurious patterns in the AGBdiversity ***:species richness,maximum height,functional richness,functional dispersion and Rao

关键词： Taxonomic diversity Functional diversity Complementarity hypothesis Mass-ratio hypothesis

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structure of the Community of Dominant Fish species Associated to soft-Bottoms in the Lagoon of La Paz, B.C.s., México

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Open Journal of Marine science 2020年第3期10卷 79-92页

作者： Bruma R. Castillo-Rosas Emelio Barjau-González Juan Manuel López-Vivas Abril Karim Romo-Piñeda Eleonora Romero-Vadillo Jose Ángel Armenta-Quintana departamento Académico de ciencias Marinas y Costeras Universidad Autónoma de Baja California Sur La Paz México departamento Académico de Ciencia Animal y Conservación del Hábitat Universidad Autónoma de Baja California Sur La Paz México

The study of fish communities from coastal lagoons allows a better understanding of role of these organisms in these systems, and the effect of anthropogenic impact. The aim of the present study was to determine the community structure, in particular dominance of fish species associated to soft bottoms in the lagoon of La Paz. six bimonthly samplings were carried out in seven localities from november 2016 to september 2017 and physicochemical parameters were recorded. Analysis of temperature showed differences between two marked seasons, warm and cold. species richness showed differences between months and localities. shannon-Weaver index and Pielou’s evenness showed significant differences only between months. simpson’s index suggests a high diversity. According to the BVI, 15 species from the families Haemulidae, sciaenidae and Gerreidae, were the most biologically important. Zoogeographic affinity analysis showed that 58% of the species prefer the Province of Cortez. Dominant species recorded in this study play a key role in soft-bottom systems like the lagoon of La Paz.

关键词： Coastal Lagoon Lagoon of La Paz Diversity Dominance

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Corrosion Behavior of Ψ and β Quasicrystalline Al–Cu–Fe Alloy

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Acta Metallurgica sinica(English Letters) 2015年第9期28卷 1117-1122页

作者： Alvaro Torres sergio serna Cristobal Patio Gerardo Rosas Facultad de ciencias Químicas e Ingeniería P.A. Ing.Mecnica UAEM Av. Universidad 1001 Col. Chamilpa62210 Cuernavaca Mor. Mexico Centro de Investigación en Ingeniería y ciencias Aplicadas UAEM Av. Universidad 1001 Col. Chamilpa62210 Cuernavaca Mor. Mexico Facultad de Ingeniería Universidad Autónoma del CarmenCampus Ⅲ Avenida Central S/N Esq. con Fracc. MundoMaya C.P. 24115 Ciudad del Carmen Campeche Mexico instituto de Investigaciones Metalurgicas UMSNH Edificio U. Ciudad Universitaria Morelia Mich. 58000 Mexico

Two nanostructured A1-Cu-Fe alloys, A164Cu24Fe12 and A162.5Cu25.2Fe12.3, have been studied. Icosahedral quasicrystalline （ψ） A164CH24FeI2 and crystalline cubic （ β） ***25.2Fe12.3 cylindrical ingots were first produced using normal casting techniques. High-energy mechanical milling was then conducted to obtain β icosahedral and β intermetallic nanostructured powders. Electrochemical impedance spectroscopy, linear polarization resistance, and potentiodynamic polarization were used to investigate the electrochemical corrosion characteristics of the powders in solutions with different pH values. Current density （icorr）, polarization resistance （Rp）, and impedance modulus （121） were determined. The results showed that regardless of pH value, increasing the solution temperature enhanced the corrosion resistance of the both phases. However, the electrochemical behavior of the phase indicated that its stability depends on the submerged exposure time in neutral and alkaline environments. This behavior was related to the type of corrosion products present on the surfaces of the particles along with the diffusion and charge-transfer mechanisms of the corrosion process.

关键词： nano-quasicrystalline AI-Cu-Fe alloy Mechanical alloying Corrosion

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Chronic Administration of the Resveratrol or n-PEP-12 Ameliorates the Endothelial Dysfunction in Aging Rats

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Pharmacology & Pharmacy 2014年第1期5卷 69-74页

作者： Gonzalo Flores Josue Hernández-Cabrera Celeste santamaria-Juarez Rubén Antonio Vázquez-Roque Elizabeth Monserrat-Hernández Ma. de Jesús Gómez-Villalobos Jorge Flores-Hernández Fausto Atonal-Flores José Gustavo López-López Facultad de ciencias Químicas Universidad Autónoma de Puebla Puebla México Facultad de ciencias Químicas Universidad Autónoma de Puebla Puebla México Facultad de Medicina Universidad Autónoma de Puebla Puebla México. instituto de Fisiología Universidad Autónoma de Puebla Puebla México instituto de Fisiología Universidad Autónoma de Puebla Puebla México

Here we investigated the effects of chronic treated with resveratrol, a polyphenol (3,4’,5-trihydroxystilbene) found in more than 70 plant species and food products such as red grapes, berries and peanuts, or n-PEP-12, a mix of peptides, on arteries in aging rats. Aging rats have shown endothelial dysfunction. Aged sprague-Dawley rats (18 months old) were treated with resveratrol (20 mg/kg/day by gavage) or n-PEP-12 (60 mg/kg/day by gavage) for 10 weeks. 24 hours after the last administration of resveratrol or n-PEP-12, the animals were weighed and diastolic and systolic blood pressure was measured by tail-cuff plethysmography. Thoracic and abdominal aorta artery segments were obtained from resveratrol-, n-PEP-12-and vehicle-treated rats and were mounted in isometric tension for isolated vessels. We found that resveratrol and n-PEP-12 improved acetylcholine-induced relaxation in the old animals. These results suggest that chronic administration of resveratrol or n-PEP-12 may in part reduce endothelial dysfunction in the aging.

关键词： Resveratrol n-PEP-12 Aging Vascular Endothelium Blood Pressure

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The first meteorological observations at a tropical high elevation site:Antisana,1846

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Journal of Mountain science 2016年第6期13卷 1047-1055页

作者： Aria Ma M.FARROnA Fernando DOMInGUEZ-CAsTRO Ma Cruz GALLEGO Jose M.VAQUERO departamento de Fisica Facultad de CienciasUniversidad de ExtremaduraBadajoz 06071Spain instituto de Fisica de Cantabria(UC-CsIC) Santander 39005Spain departamento de Ingenieria Civily Ambiental Escuela Politecnica NacionalQuito 170112Ecuador instituto nacional de Meteorologiae Hidrologia Quito 170135Ecuador instituto universitario de investigación del agua cambio climático y sostenibilidad (iacys) universidad de extremaduraBadajoz 06071，Spain departamento de física centro universitario de mérida universidad de extremaduraMerida 06800Spain

Antisana is a stratovolcano with an associated glacier located in the Ecuadorian Andes. Dr Aguirre made meteorological readings every day, at every hour from sunrise to sunset, from december 1845 to december 1846, at Antisana using a meteorological station at 4060 mamsl （meters above mean sea level）. Unfortunately, only the monthly average data have been preserved. These meteorological data are here studied and compared with the closest modern stations for monthly values of temperature, rainfall, and pressure. According to these comparisons, the year 1846 was rainy and cold in comparison with the current climate. Moreover, these observations have been useful to help resolve a debate about a possible E1nifio event in 1846 with the high precipitation in Antisana and Quito in 1846 discarding the occurrence of an E1 nifio event. The probable occurrence of a La nifia event is discussed. These data are the earliest known systematic instrumental meteorological observations taken at above 4000 mamsl.

关键词： Early instrumental records Glacier Pastclimate conditions

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Multi-temporal nDVI analysis using UAV images of tree crowns in a northern Mexican pine-oak forest

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Journal of Forestry Research 2023年第6期34卷 1855-1867页

作者： JoséLuis Gallardo-salazar Marcela Rosas-Chavoya Marín Pompa-García Pablito Marcelo López-serrano Emily García-Montiel Arnulfo Meléndez-soto sergio Iván Jiménez-Jiménez instituto de Investigaciones agropecuarias y Forestales Universidad Michoacana de San Nicolás de Hidalgo(UMSNH)58330 MoreliaMichoacánMexico Programa Institucional de Doctorado en ciencias agropecuarias y Forestales Universidad Juárez del Estado de DurangoRío Papaloapan y Blvd.DurangoValle del Sur s/n34120 DurangoDurangoMéxico Facultad de ciencias Forestales Universidad Juárez del Estado de DurangoRío Papaloapan y Blvd.DurangoValle del Sur s/n34120 DurangoDurangoMéxico instituto de silvicultura e Industria de la Madera Universidad Juárez del Estado de DurangoBoulevard del Guadiana 501Ciudad UniversitariaTorre de Investigación34120 DurangoMéxico InIFAP-CEnID RAsPA Centro nacional de Investigación Disciplinaria en Relación Agua-suelo-Planta-Atmósfera Margen derecha canal Sacramento km 6.5Zona industrial35140 Gómez PalacioDurangoMexico

The use of unmanned aerial vehicles(UAV)for forest monitoring has grown significantly in recent years,providing information with high spatial resolution and temporal *** with multispectral sensors allow the use of indexes such as the normalized difference vegetation index(nDVI),which determines the vigor,physiological stress and photo synthetic activity of *** study aimed to analyze the spectral responses and variations of nDVI in tree crowns,as well as their correlation with climatic factors over the course of one *** study area encompassed a 1.6-ha site in Durango,Mexico,where Pinus cembroides,Pinus engelmannii,and Quercus grisea *** images were acquired with UAV and information on meteorological variables was obtained from nAsA/POWER *** AnOVA explored possible differences in nDVI among the three *** correlation was performed to identify the linear relationship between nDVI and meteorological *** differences in nDVI values were found at the genus level(Pinus and Quercus),possibly related to the physiological features of the species and their *** grisea had the lowest nDVI values throughout the year which may be attributed to its sensitivity to relative humidity and *** the use of UAV with a multispectral sensor for nDVI monitoring allowed genera differentiation,in more complex forest analyses hyperspectral and LiDAR sensors should be integrated,as well other vegetation indexes be considered.

关键词： Multispectral images normalized diff erence Vegetation index Phenology Unmanned aerial vehicles Multitemporal analysis

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Driving factors behind multiple populations

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science China(Physics,Mechanics & Astronomy) 2024年第5期67卷 172-181页

作者： Ruoyun Huang Baitian Tang Chengyuan Li Doug Geisler Mario Mateo Ying-Yi song Holger Baumgardt Julio A.Carballo-Bello Yue Wang Jundan nie Bruno Dias JoséG.Fernández-Trincado school of Physics and Astronomy Sun Yat-sen UniversityZhuhai 519082China CssT science Center for the Guangdong-Hong Kong-Macao Greater Bay Area Zhuhai 519082China departamento de Astronomía Universidad de ConcepcionConcepcionChile instituto de Investigación Multidisciplinario en Ciencia y Tecnología Universidad de La SerenaLa SerenaChile departamento de Astronomía Facultad de CienciasUniversidad de La SerenaChile department of Astronomy University of MichiganAnn Arbor 48109USA David A.Dunlap department of Astronomy&Astrophysics University of TorontoToronto ON M5S 3H4Canada Dunlap Institute for Astronomy&Astrophysics University of TorontoToronto ON M5S 3H4Canada school of Mathematics and Physics The University of QueenslandSt.Lucia QLD 4072Australia instituto de Alta Investigación Universidad de TarapacáAricaChile CAs Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China instituto de Astrofísica Departamento de Ciencias FísicasFacultad de Ciencias ExactasUniversidad Andres BelloSantiagoChile instituto de Astronomía Universidad Católica del NorteAntofagastaChile

star clusters were historically considered simple stellar populations,with all stars sharing the same age and initial chemical ***,the presence of chemical anomalies in globular clusters(GCs),called multiple stellar populations(MPs),has challenged star formation theories in dense *** studies show that mass,metallicity,and age are likely controlling parameters for the manifestation of *** the limit between clusters with/without MPs in physical parameter space is crucial to reveal the driving mechanism behind their *** this study,we look for MP signals in Whiting 1,which is traditionally considered a young *** the Magellan telescope,we obtained low-resolution spectra withinλλ=3850-5500?for eight giants of Whiting *** measured the C and n abundances from the Cn and CH spectral indices.C and n abundances have variations comparable with their measurement errors(~0.1 dex),suggesting that MPs are absent from Whiting *** these findings with literature studies,we propose a limit in the metallicity *** compactness index parameter space,which relatively clearly separates star clusters with/without MPs(GCs/open clusters).This limit is physically *** a larger scale,the galactic environment determines cluster compactness and metallicity,leading to metal-rich,diffuse,old clusters formed ex *** proposed limit also impacts our understanding of the formation of the sagittarius dwarf galaxy:star clusters formed after the first starburst(age≤8-10 Gyr).These clusters are simple stellar populations because the enriched galactic environment is no longer suitable for MP formation.

关键词： stellar galactic galaxy

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Impacts of brood parasitism by shiny cowbird Molothrus bonariensis on the breeding success of a small host, the black-backed water tyrant Fluvicola albiventer

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Current Zoology 2024年第4期70卷 539-547页

作者： Lorena Vanesa sovrano Evelina Jesica Leon Rodrigo Ezequiel Lorenzón Pamela Fernanda Olguin Adolfo Héctor Beltzer Alejandro Raúl Giraudo Laboratorio de Biodiversidad y Conservacion de Tetrapodos Instituto Nacional de Limnologia(INALICONICET-UNL)Paraje El Pozo s/nSanta Fe(3000)Argentina departamento de Biologia Universidad Autonoma de Entre RiosKm 10.5 RP 11Oro Verde(3100)Entre RiosArgentina departamento de Biologia Universidad Nacional del LitoralFacultad de Humanidades y CienciasParaje Ei Pozo s/nSanta Fe(3000)Argentina

The shiny cowbird Molothrus bonariensis parasitizes many species with different life-history traits and has a detrimental effect on the survival of the progeny of the *** response,hosts have developed numerous antiparasitic ***,we examined the effects of brood parasitism by shiny cowbird on the clutch and brood sizes(83 nests)in a small host,the black-backed water tyrant Fluvicola *** also studied whether the death of parasite nestlings was related to the care of the foster parents and whether the host had any antiparasitic defense against the shiny *** results indicate that brood parasitism significantly decreased the host hatching and fledging *** majority of nest failures(57%)were caused by brood *** cowbird parasitism occurred in 52%of nests and the intensity of parasitism was 1.23±0.53 eggs per parasitized *** the total host eggs,54%were *** the incubation stage,20 nests(47%)were abandoned because of egg punctures by shiny cowbirds *** two parasitic fledglings were recorded,while the remaining nestlings either died from starvation(n=12)or predation(n=3).Foster parents abandoned parasitic nestlings between 5 and 10 days *** findings demonstrate that the shiny cowbird has very low rates of fledging success when parasitizing black-backed water ***,parasitism had a high reproductive cost in the black-backed water tyrant because a very low proportion(7%)of the parasitized nests(n=43)were successful.

关键词： brood parasitism host defenses nest desertion shiny cowbird small host.

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Highly graphitized carbon nanosheets with embedded ni nanocrystals as anode for Li-ion batteries

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nano Research 2020年第1期13卷 86-94页

作者： Francisco Javier soler-Piña Celia Hernández-Rentero Alvaro Caballero Julián Morales Enrique Rodríguez-Castellón Jesús Canales-Vázquez Dpto.Química Inorgánica e Ingeniería Química Instituto de Química Fina y NanoquímicaUniversidad de Córdoba14071CórdobaSpain Dpto.Química Inorgánica Cristalografía y MineralogíaFacultad de CienciasUniversidad de Málaga29071MálagaSpain instituto de Energías Renovables Universidad de Castilla-La ManchaPaseo de La Investigación 102071AlbaceteSpain

A C/ni composite was prepared via thermal decomposition of a nickel oleate complex at 700℃,yielding disperse ni nanocrystals with an average size of 20 nm,encapsulated by carbon nanosheets as deduced from transmission electron microscopy(TEM)images and confirmed from X-ray photoelectron spectroscopy(XPs).Furthermore,the X-ray diffraction pattern revealed a good ordering of the carbon layers,forced by the ni encapsulation to adopt a bending *** the close interaction between the graphitized framework and the metallic nanoparticles we have studied the properties of the composite as an anode for Li-ion *** with other nanostructured synthetic carbons,this carbon composite has a low voltage hysteresis and a modest irreversible capacity value,properties that play a significant role in its behaviour as electrodes in full cell *** moderate rate values,0.25 C,the electrode delivers an average capacity value around 723 mAh·g^−1 on cycling,among the highest values so far reported for this carbon *** higher rate values,1 C,the average capacity values delivered by the cell on cycling decrease,around 205 mAh·g^−1,but it maintains good capacity retention,a coulombic efficiency close to 100%after the first cycles and recovery of the capacity values when the rate is restored from 3 to 0.1 C.

关键词： carbon nanosheets nickel nanoparticles anode lithium batteries

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