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Geomorphic indices and relative tectonic uplift in the Guerrero sector of the Mexican forearc

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Geoscience Frontiers 2017年第4期8卷 885-902页

作者： Krzysztof Gaidzik María Teresa Ramírez-Herrera Laboratorio Universitario de Geofísica Ambiental & instituto de geografía Universidad Nacional Autónoma de MéxicoCiudad Universitaria Berkeley Seismological Laboratory Department of Earth and Planetary ScienceUniversity of California Berkeley

Tectonically active areas,such as forearc regions,commonly show contrasting relief,differential tectonic uplift,variations in erosion rates,in river incision,and in channel gradient produced by ongoing tectonic deformation.Thus,information on the tectonic activity of a defined area could be derived via landscape analysis.This study uses topography and geomorphic indices to extract signals of ongoing tectonic deformation along the Mexican subduction forearc within the Guerrero sector.For this purpose,we use field data,topographical data,knickpoints,the ratio of volume to area（Rva）.the stream-length gradient index（St）,and the normalized channel steepness index（k_（sn））.The results of the applied landscape analysis reveal considerable variations in relief,topography and geomorphic indices values along the Guerrero sector of the Mexican subduction zone.We argue that the reported differences are indicative of tectonic deformation and of variations in relative tectonic uplift along the studied forearc.A significant drop from central and eastern parts of the study area towards the west in values of R_（VA）（from ~500 to^300）,St（from ~500 to ca.400）,maximum St（from ~1500-2500 to ~ 1000） and k_（sn）（from ~150 to ~100） denotes a decrease in relative tectonic uplift in the same direction.We suggest that applied geomorphic indices values and forearc topography are independent of climate and lithology.Actual mechanisms responsible for the observed variations and inferred changes in relative forearc tectonic uplift call for further studies that explain the physical processes that control the forearc along strike uplift variations and that determine the rates of uplift.The proposed methodology and results obtained through this study could prove useful to scientists who study the geomorphology of forearc regions and active subduction zones.

关键词： Relative tectonic uplift Forearc Active tectonics Geomorphic index Drainage network Mexican subduction zone

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

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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 communities.Differences 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

Coyote(Canis latrans)in South America:potential routes of colonization

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Integrative Zoology 2020年第6期15卷 471-481页

作者： Octavio MONROY-VILCHIS JoséF.GONZÁLEZ-MAYA Ángel BALBUENA-SERRANO Fausto ELVIR Martha M.ZARCO-GONZÁLEZ Clarita RODRÍGUEZ-SOTO Centro de Investigación en Ciencias Biológicas Aplicadas Universidad Autónoma del Estado de MéxicoInstituto Literario 100TolucaMéxico50000México instituto de Ecología Universidad Nacional Autónoma de MéxicoCoyoacánMéxico The Sierra to Sea Institute and ProCAT Colombia Las AlturasCoto BrusPuntarenasCosta Rica Fundación Investigación en Ciencias para el Estudio y Conservación de la Biodiversidad Instituto de Ciencia para el Estudio y Conservación de la Biodiversidadfrente a la Escuela República de JapónTegucigalpaHonduras Facultad de geografía Universidad Autónoma del Estado de MéxicoInstituto Literario 100TolucaMéxico50000México

During the last century,the coyote(Canis latrans)has increased its distribution in Central America.Before the 1980s,it had not been recorded in Panama.New records show that coyotes have crossed the Panama Canal,indicating that continues to expand;therefore,there is a possibility that it will reach northern South America.Our objectives were to identify potential coyote colonization routes to South America,and the variables that favor its expansion.We hypothesized that habitat fragmentation benefits coyote expansion.We applied 7 algorithms to model the potential distribution of the coyote,using 196 presence records and 12 variables.The models with better performance were used to generate a consensus model.Using our consensus model and the areas with highest probability of presence,a potential colonization route was generated between Central America and northern South America.This route lies through southern Costa Rica,along the Pacific coast of Panama to the south,to the Andean mountains in northern Colombia.The variables that explained potential coyote distribution were human population density,altitude,and percentage of crops with positive influence,and tropical broadleaf forests with negative in-fluence.These results indicate that human activities and deforestation are related to coyote distribution expansion.Actions can be implemented within the identified route to improve environmental management,in order to avoid the presence of the coyote in the ecosystems of northern South America.

关键词： Canis latrans carnivore distribution expansion invasive management species distribution model

Landform Instability and Land-use Dynamics in Tropical High Mountains, Central Mexico

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Journal of Mountain Science 2012年第3期9卷 414-430页

作者： GARCíA-ROMERO Arturo ACEVES-QUESADA José Fernando ARREDONDO-LEóN Carlos departamento de geografía Física Instituto de Geografía Universidad Nacional Autónoma de México. Circuito exterior s/n Ciudad Universitaria 04510 Mexico Distrito Federal Mexico Unidad Académica de Estudios Regionales de la Coordinación de Humanidades Universidad Nacional Autónoma de México

This investigation is an analysis of the influence of landform instability on the distribution of land-use dynamics in a hydrographical basin, located in the Mexican Volcanic Belt mountain range (central Mexico), currently affected by substantial changes in land use and deforestation. A landform map was produced, in addition to seven attribute maps - altimetry, drainage density, slope, relief energy, potential erosion, geology and tectonics - which were considered as factors for determining landform instability through Multi-criteria Evaluation Analysis. Likewise, the direction and rhythm of land-use dynamics were analyzed in four dates - between 1976 and 2000 - and cross tabulations were made between them, in order to analyze the trends and processes of land-use dynamics. Afterwards, the databases obtained were cross tabulated with the landform variables to derive areas, percentages and correlation indices. In the study area, high-instability landforms are associated with most ancient volcanic and sedimentary landforms, where high altitude, drainage density, slope and potential to develop gravitational and fluvial processes are the major factors favouring a land-use pattern, dominated by the conservation of extensive forest land, abandonment of human land use and regeneration of disturbed areas. In contrast, low-instability landforms correspond to alluvial plains and lava hills covered by pyroclasts, where low potential erosion to develop fluvial processes, added to water and soil availability and accessibility, have favoured a land-use pattern dominated by the expansion of agroforestry plantations and human settlements, showing a marked trend towards either intensification or permanence of the current land use and with little abandonment and regeneration.

关键词：土地利用模式不稳定地形图墨西哥热带土地利用现状森林砍伐河网密度

PANoptosis:new insights in regulated cell death in ischemia/reperfusion models

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Neural Regeneration Research 2023年第2期18卷 342-343页

作者： Paloma González-Rodríguez Arsenio Fernández-López Área de Biología Celular Instituto de BiomedicinaUniversidad de LeónSpain

See related article,pp 357-363The first study describing the cell death and destruction of tissues,organs,and organ systems as programmed events during the development of multicellular organisms was performed by JW Saunders Jr in 1966.The term apoptosis was introduced by Kerr,Wyllie,and Currie in 1972 to describe a programmed phenomenon opposite to mitosis in the regulation of animal cell populations.Later,a description of ectodermal cell lineages as programmed cell death in the worm Caenorhabditis elegans was publishedby JE Sulston and HR Horvitz in 1976.

关键词： organs insight opposite

Biaxial versus uniaxial strain tuning of single-layer MoS2

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Nano Materials Science 2022年第1期4卷 44-51页

作者： Felix Carrascoso Riccardo Frisenda Andres Castellanos-Gomez Materials Science Factory Instituto de Ciencia de Materiales de Madrid (ICMM-CSIC)

Strain engineering has arisen as a powerful technique to tune the electronic and optical properties of two-dimensional semiconductors like molybdenum disulfide(MoS). Although several theoretical works predicted that biaxial strain would be more effective than uniaxial strain to tune the band structure of MoS, a direct experimental verification is still missing in the literature. Here we implemented a simple experimental setup that allows to apply biaxial strain through the bending of a cruciform polymer substrate. We used the setup to study the effect of biaxial strain on the differential reflectance spectra of 12 single-layer MoSflakes finding a redshift of the excitonic features at a rate between-40 me V/% and-110 me V/% of biaxial tension. We also directly compare the effect of biaxial and uniaxial strain on the same single-layer MoSfinding that the biaxial strain gauge factor is 2.3 times larger than the uniaxial strain one.

关键词： 2D materials MoS2 Strain engineering biaxial strain uniaxial strain reflectance spectra

SPINOPHILIN: A multiplayer tumor suppressor

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Genes & Diseases 2023年第1期10卷 187-198页

作者： Eva M.Verdugo-Sivianes Amancio Carnero instituto de Biomedicina de Sevilla IBISHospital Universitario Virgen del RocioConsejo Superior de Investigaciones CientificasUniversidad de SevillaSeville 41013Spain CIBERONC Instituto de Salud Carlos IlMadrid 28029Spain

SPINOPHILIN(SPN,PPP1R9B or NEURABIN-2)is a multifunctional protein that regulates protein-protein interactions in different cell signaling pathways.SPN is also one of the regulatory subunits of protein phosphatase 1(PP1),implicated in the dephosphorylation of retinoblastoma protein(pRB)during cell cycle.The SPN gene has been described as a tumor suppressor in different human tumor contexts,in which low levels of SPN are correlated with a higher grade and worse prognosis.In addition,mutations of the SPN protein have been reported in human tumors.Recently,an oncogenic mutation of sPN,A566V,was described,which affects both the SPN-PP1 interaction and the phosphatase activity of the holoenzyme,and promotes p53-dependent tumorigenesis by increasing the cancer stem cell(CsC)pool in breast tumors.Thus,the loss or mutation of SPN could be late events that promotes tumor progression by increasing the CSC pool and,eventually,the malignant behavior of the tumor.

关键词： Cancer therapy Phosphatase PP1 SPINOPHILIN Tumor suppressor Tumorigenesis

Enzymatic and chemo-enzymatic strategies to produce highly valuable chiral amines from biomass with ω-transaminases on 2D zeolites

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National Science Review 2022年第9期9卷 10-18页

作者： J.Miguel Carceller Karen S.Arias Maria J.Climent Sara Iborra Avelino Corma instituto de Tecnologia Química (UPV-CSIC) Universitat Politècnica de València

Amino transaminases(ATAs) have been supported on a 2D ITQ-2 zeolite through electrostatic interactions, resulting in a highly stable active biocatalyst to obtain a variety of valuable chiral amines starting from prochiral ketones derived from biomass. We have extended the biocatalyst applications by designing a chemo-enzymatic process that allows, as the first step, prochiral ketones to be obtained from biomass-derived compounds through an aldol condensation–reduction step using a bifunctional metal/base catalyst. The prochiral ketone is subsequently converted into the chiral amine using the immobilized ATA. We show that it is feasible to couple both steps in a semi-continuous process to produce industrially relevant chiral amines with yields of >95% and ～100% enantiomer excess.

关键词： amino transaminase ITQ-2 zeolite chemo-enzymatic process biomass semi-continuous process Pd/MgO

Natural sediment at a dam and its inorganic materials as adsorbents of praseodymium(Pr(Ⅲ))

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International Journal of Sediment Research 2023年第4期38卷 566-575页

作者： Melania Jiménez-Reyes Jaime Jiménez-Becerril Marcos Solache-Ríos Perla Tatiana Almazán-Sánchez departamento de Química Instituto Nacional de Investigaciones Nucleares Carretera México-Toluca S/N CONACy T-instituto Nacional de Investigaciones Nucleares

The sediment deposited behind a dam(DS) and its inorganic materials(IM-DS) were characterized and used for the removal of praseodymium(Pr) from aqueous solutions. Quartz, albite, and kaolinite were found in the sediment by X-ray diffraction. Kinetic data fit well to a pseudo second-order model, the equilibrium time for DS and IM-DS was 2 h and 3 min, respectively, and the adsorption capacity was higher for Pr/DS(qe= 4.91 mg/g) than for Pr/IM-DS(qe= 3.01 mg/g) in these conditions. Pr/DS and Pr/IM-DS data isotherms were in agreement with the Langmuir-Freundlich model and the maximum adsorption capacities were 4.95 and 4.01 mg/g, respectively. Both processes are exothermic(enthalpy change, ΔH0=-22.8 and-21.8 k J/mol for DS and IM-DS, respectively), the increase of the randomness is small, and the feasibility and spontaneity are low. Praseodymium was desorbed by ethylenediaminetetraacetic acid disodium(EDTA-Na2), sodium chloride, nitric, citric, and humic acids solutions, and one hundred percent of praseodymium was desorbed by the EDTA-Na2solution. The Pr2(EDTA)3(praseodymium ethylenediaminetetraacetate) complex was completely desorbed from both materials(DS and IM-DS). Distribution coefficients(KD) depend upon praseodymium concentration,temperature, p H, and the kind of adsorbent. Chemical reactions of praseodymium with kaolinite and iron minerals could explain the adsorption.

关键词： Praseodymium Sediment Adsorption process parameters desorption