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Landslide susceptibility: a statistically-based assessment on a depositional pyroclastic ramp

Journal of Mountain Science 2019年第3期16卷 561-580页

作者： Franny G.murillo-garcíA Stefan STEGER Irasema ALCáNTARA-AYALA Institute of Geography National Autonomous University of Mexico (UNAM) Institute for Earth Observation Eurac Research

This study aimed to produce a high-quality landslide susceptibility map for Teziutlán municipality, a landslide-prone region in Mexico, which is characterised by a depositional pyroclastic ramp. The heterogeneous quality of available topographic information(i.e. higher resolution digital elevation model only for a sub-region) encouraged to confront modelling results based on two different study area delineations and two raster resolutions. Input data was based on the larger modelling region L15(163 km2) and smaller S(70 km2; located inside L15) with an associated raster cell size of 15 m(region L15 and S15) and 5 m(region S5). The resulting three data sets(L15, S15 and S5) were included into three differently flexible modelling techniques(Generalized Linear Model-GLM, General Additive Model-GAM, Support Vector Machine-SVM) to produce nine landslide susceptibility models. Preceding variable selection was performed heuristically and supported by an exploratory data analysis. The final models were based on the explanatory variables slope angle, slope aspect, lithology, relative slope position, elevation, convergence index, distance to streams, distance to springs and topographic wetness index. The ability of the models to classify independent test data was elaborated using a k-fold cross validation procedure and the AUROC(Area Under the Receiver Operating Characteristic) metric. In general, all produced landslide susceptibility maps depicted the hillslopes of the ravines, which cut the pyroclastic ramp, as prone to landsliding. The modelling results showed that predictive performances(i.e. AUROC values) slightly increased with an increasing flexibility of the applied modelling technique. Thus, SVM performed best, while the GAM outperformed the GLM. This tendency was most distinctive when modelling with the largest landslide sample size(i.e. data set L15; n = 662 landslides). Non-linear classifiers(GAMs, SVMs) performed slightly better when trained on the basis of lower

关键词： Landslide susceptibility Pyroclastic ramp Logistic regression Generalized Additive Model Support Vector Machine Cross validation

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Hydrothermal Synthesis and Characterization of Europium-doped Barium Titanate Nanocrystallites

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Nano-Micro Letters 2013年第1期5卷 57-65页

作者： Margarita garcía-Hernndez Geneviève Chadeyron Damien Boyer Antonieta garcía-murillo Felipe Carrillo-Romo Rachid Mahiou Universidad Autónoma Metropolitana Departamento de Ciencias NaturalesDCNIUnidad CuajimalpaPedro Antonio de los Santos 8411850 Mxico D.F. Mxico Clermont Universit Institut de Chimie de Clermont-Ferrand UMR 6296CNRS/UBP/ENSCCFBP 10448F-63000 Clermont-Ferrand Instituto Politcnico Nacional CIITEC IPNCerrada de Cecati S/N. Col. Santa CatarinaAzcapotzalco Mxico D.F. C.P. 02250Mxico

Barium titanate nanocrystallites were synthesized by a hydrothermal technique from barium chloride and tetrabutyl titanate. Single-crystalline cubic perovskite Ba TiO_3 consisting of spherical particles with diameters ranging from 10 to 30 nm was easily achieved by this route. In order to study the influence of the synthesis process on the morphology and the optical properties, barium titanate was also prepared by a solid-state reaction. In this case, only the tetragonal phase which crystallizes above 900 was observed. High-temperature X-ray diffraction measurements were performed to investigate the crystallization temperatures as well as the particle sizes via the Scherrer formula. The lattice vibrations were evidenced by infrared spectroscopy. Eu^(3+)was used as a structural probe, and the luminescence properties recorded from Ba TiO_3 :Eu^(3+)and elaborated by a solid-state reaction and hydrothermal process were compared. The reddish emission of the europium is increased by the nanometric particles.

关键词： BaTiO3 Europium Nanocrystallites Hydrothermal technique

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Comparative mitogenome phylogeography of two anteater genera (Tamandua and Myrmecophaga;Myrmecophagidae, Xenarthra): Evidence of discrepant evolutionary traits

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Zoological Research 2021年第5期42卷 525-547页

作者： Manuel Ruiz-garcía Daniel Pinilla-Beltrán Oscar E.murillo-garcía Christian Miguel Pinto Jorge Brito Joseph Mark Shostell Laboratorio de Genética de Poblaciones Molecular-Biología Evolutiva Departamento de BiologíaFacultad de CienciasPontificia Universidad JaverianaBogotáDC 110231Colombia Grupo de Investigación en Ecología Animal Departamento de BiologíaFacultad de Ciencias Naturales y ExactasUniversidad del ValleApartado AéreoCali 25360Colombia Instituto de Ciencias Biológicas Escuela Politécnica NacionalQuito 17012759Ecuador Instituto Nacional de Biodiversidad(INABIO) Quito 170135Ecuador Math Science and Technology DepartmentUniversity of Minnesota CrookstonCrookstonMN 56716USA

The species within Xenarthra(sloths,anteaters,and armadillos)are quintessential South American *** the three groups,Vermilingua(anteaters)contains the fewest extant and paleontological ***,we sampled and sequenced the entire mitochondrial genomes(mitogenomes)of two Tamandua species(Tamandua tetradactyla and ***)(n=74)from Central and South America,as well as Myrmecophaga tridactyla(n=41)from South *** Tamandua,we detected three different *** oldest(THI)contained many specimens with the *** morphotype(but also several with the *** morphotype)and originated in southeastern South America(currently Uruguay)before moving towards northern South America,where the THII haplogroup *** primarily contained specimens with the *** morphotype(but also several with the *** morphotype)and was distributed in Central America,Colombia,and *** and THII yielded a genetic distance of 4%.THII originated in either northern South America or“in situ”in Central America with haplogroup THIII,which consisted of~50%*** and 50%*** *** was mostly located in the same areas as THII,i.e.,Central America,Ecuador,and Colombia,though mainly in the *** three haplogroups overlapped in Colombia and ***,*** and *** were not reciprocally *** this reason,we considered that a unique species of Tamandua likely exists,i.e.,*** contrast to Tamandua,*** did not show different morphotypes throughout its geographical range in the ***,two very divergent genetic haplogroups(MHI and MHII),with a genetic distance of~10%,were *** basal haplogroup,MHI,originated in northwestern South America,whereas the more geographically derived haplogroup,MHII,overlapped with MHI,but also expanded into central and southern South ***,Tamandua migrated from south to north whereas Myrmecophaga migrated from

关键词： Anteaters Genetic diversity Mitogenomes Myrmecophaga Neotropics Phylogeography Spatial structure Tamandua

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Effect of the filling season on aquatic plants in Mediterranean temporary ponds

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Journal of Plant Ecology 2018年第3期11卷 502-510页

作者： Rocío Fernández-Zamudio Pablo garcía-murillo Carmen Díaz-Paniagua Doñana Biological Station-CSIC Avda.Américo Vespucio s/n41092 SevilleSpain Department of Plant Biology and Ecology Faculty of PharmacyUniversity of SevilleSevilleSpain

Aims Pond environmental conditions may differ among years with regards to the season in which ponds begin to *** experimen-tally evaluated how seedling emergence,plant growth and phe-nology differed among years in which filling occurred in winter,autumn or *** We collected sediments from a natural temporary pond and located them in *** were placed in a climatic chamber that simulated annual variation in field environmental temperatures and light *** were assigned to one of three treat-ments,which differed in the date on which they were filled with water(autumn,winter and spring).We counted the number of seed-lings of different species emerged and recorded data about the pres-ence of flowers,seeds or spores every *** experiment was finished in June,when we harvested the plants and estimated their *** Findings In most species,seedling emergences were primarily related to time after filling,and thus synchronized their life cycles with the unpre-dictably timed wet phase of the *** filling resulted in the highest numbers of seeds/***,winter filling pro-moted plant growth the *** the spring filling treatment,more terrestrial plant seedlings emerged and fewer seeds/spores were *** ponds are flooded earlier,plants may produce a higher number of ***,in years when inundation is delayed to spring and hydroperiods are short,seedling emergence deplete the seed bank and there is little to no seed production,while terrestrial monocots are able to colonize pond basin.

关键词： Aquatic plants temporary ponds seed bank seedlings germination

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Hazard and population vulnerability analysis: a step towards landslide risk assessment

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Journal of Mountain Science 2017年第7期14卷 1241-1261页

作者： Franny G.murillo-garcíA Mauro ROSSI Francesca ARDIZZONE Federica FIORUCCI Irasema ALCáNTARA-AYALA Postgraduate in Geography National Autonomous University of Mexico (UNAM) IRPI CNR Institute of Geography National Autonomous University of Mexico (UNAM)

In this paper, an attempt to analyse landslide hazard and vulnerability in the municipality of Pahuatlfin, Puebla, Mexico, is presented. In order to estimate landslide hazard, the susceptibility, magnitude （area-velocity ratio） and landslide frequency of the area of interest were produced based on information derived from a geomorphological landslide inventory; the latter was generated by using very high resolution satellite stereo pairs along with information derived from other sources （Google Earth, aerial photographs and historical information）. Estimations of landslide susceptibility were determined by combining four statistical techniques：（i） logistic regression, （ii） quadratic discriminant analysis, （iii） linear discriminant analysis, and （iv） neuronal networks. A Digital Elevation Model （DEM） of lo m spatial resolution was used to extract the slope angle, aspect, curvature, elevation and relief. These factors, in addition to land cover, lithology anddistance to faults, were used as explanatory variables for the susceptibility models. Additionally, a Poisson model was used to estimate landslide temporal frequency, at the same time as landslide magnitude was obtained by using the relationship between landslide area and the velocity of movements. Then, due to the complexity of evaluating it, vulnerability of population was analysed by applying the Spatial Approach to Vulnerability Assessment （SAVE） model which considered levels of exposure, sensitivity and lack of resilience. Results were expressed on maps on which different spatial patterns of levels of landslide hazard and vulnerability were found for the inhabited areas. It is noteworthy that the lack of optimal methodologies to estimate and quantify vulnerability is more notorious than that of hazard assessments. Consequently, levels of uncertainty linked to landslide risk assessment remain a challenge to be addressed.

关键词： Landslides Susceptibility HazardVulnerability Risk

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Structural studies of BaTiO_3:Er^(3+) and BaTiO_3:Yb^(3+) powders synthesized by hydrothermal method

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Journal of Rare Earths 2014年第11期32卷 1016-1021页

作者： Garrido-Hernández A garcía-murillo a Carrillo-Romo F de J Cruz-Santiago L A Chadeyron G Morales-Ramírez A de J Velumani S T.A. Post-graduate Student. Instituto Politécnico Nacional CIITEC IPN Cerrada de Cecati S/N. Col. Santa Catarina Azcapotzalco México D.F. C.P. 02250 México D.F México Instituto Politécnico Nacional CIITEC IPN Cerrada de Cecati S/N. Col. Santa Catarina Azcapotzalco México D.F. C.P. 02250 México D.F Departament of Engineering Materials Tecnológico de Estudios Superiores de Coacalco (TESCo) Av. 16 de Septiembre # 54 Cabecera Municipal C.P. 55700 Coacalco de Berriozábal Estado de México Institut de Chimie de Clermont-Ferrand UMR 6296 CNRS / UBP / ENSCCF 24 avenue des Landais BP 80026 63171 Aubière Cedex – France Department of Electrical Engineering (SEES) Centro de Investigación y de Estudios Avanzados del IPN Av. Instituto Politécnico Nacional 2508 Col. San Pedro Zacatenco C.P. 07360 Mexico D.F. Mexico

Erbium and ytterbium doped barium titanate nanopowders were prepared using the hydrothermal method. A barium titanate structure doped with rare earth ions manifested new characteristics and improved the field of application of optical devices such as trichromatic tubes, LCD displays, lamps, and infrared lasers. In this work, BaTiO3：Er3＋ and BaTiO3：Yb3＋ were prepared using barium chloride [BaCl2], titanium butoxide [C16H36O4Ti], erbium chloride [ErCl3] and ytterbium chloride [YbCl3] as precursors. Anhydrous methanol was employed as a solvent. Metallic potassium was used to promote solubility in the system and increase the pH to 13. This method yielded the formation of a predominantly cubic structure in both Er3＋ and Yb3＋ doped BaTiO3 powders. Characteristic bondings of BaTiO3 were observed with FT-IR spectroscopy. The predominantly cubic structure was confirmed by X-ray diffraction and micro-Raman analyses. The particle size（～30 nm） was estimated using the Scherrer equation and X-ray diffraction data. The results were presented and discussed.

关键词： nanopowders hydrothermal BaTiO3:Er3+ BaTiO3:Yb3+ rare earths

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A Structural and Morphological Study of LiCo_1-XSm_XO_Y Powders Obtained by the Sol-Gel Method

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Advances in Nanoparticles 2022年第1期11卷 1-12页

作者： Víctor H. Colín Calderón Antonieta garcía murillo Felipe de Jesus Carrillo Romo Arturo Cervantes Tobón Instituto Politécnico Nacional CIITEC Cerrada de Cecati s/n Azcapotzalco Santa Catarina México Instituto Politécnico Nacional-ESIQIE Av. Instituto Politécnico Nacional s/n. Mexico City México

In this study, the synthesis of LiCo1-XSmXOy powders (X = 0.002, 0.004, 0.006, 0.008, and 0.1) by the sol-gel method and the influence of Sm on their structural and morphological properties is reported for the first time. The results of x-ray diffraction (XRD) studies show that LiCoO2 powders synthesized at temperatures up to 700°C present a characteristic hexagonal crystalline phase of the α-NaFeO2 type (space group R-3m), revealing a shift in the (0 0 3) Bragg reflection, which reflects the presence of Sm in the crystalline structure. The morphology was spheroidal and, on average, 122 nm in size. Based on the data obtained, LiCo1-XSmXOy powders (X = 0.002, 0.004, 0.006, 0.008, and 0.1) show promise as a material for use in the cathodes of lithium-ion batteries.

关键词： Cathode Batteries Samarium Sol-Gel Nanoparticles

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An Unusual Organometallic Supramolecule Composed of Chiral Dirhodium Units and Sulfato Bridging Ligands

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Chinese Journal of Structural Chemistry 2011年第11期30卷 1569-1574页

作者：陈进余荣民 murillo Carlos A State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences Department of Chemistry Texas A&M University PO Box 30012 College Station

A chiral supramolecular compound （H3O）{[cis-Rh2（（C6H5）2P（C6H4））2（SO4）- （DMF）]2（μ- OC2H5）}·6C2H5OH （1） has been synthesized and characterized by X-ray single-crystal analysis. Compound 1 crystallizes in monoclinic, space group C2/c with a = 26.752（3）, b = 13.5868（16）, c = 26.611（3） A, β = 103.891（2）°, V= 9389.5（19）A^3, Z = 4, C92H114N2O18P4Rh4, Mr = 2135.49, Dc = 1.511 g/cm^3, F（000） = 4384 and μ（MoKa） = 0.870 mm^-1. The final R = 0.0441 and wR = 0.1186 for 8283 observed reflections with I 〉 2σ（I） and R = 0.0567 and wR = 0.1290 for all data. The structure of the compound is unique. It contains two inherent chiral {c/s-Rh2[（C6H5）2P（C6H4）]2}^2＋ units which are connected not only in the equatorial positions by two sulfato ligands, but also in two of their axial positions by a μ2 ethoxide anion. The remaining axial positions of Rh2^4＋ units in 1 are occupied by the DMF molecules. The sulfato ligands act as P4 tridentate bridges to connect the Rh2^4＋ units. The Rh-Rh metal-metal bond distances are comparable to those in analogous dirhodium compounds.

关键词： chiral dirhodium orthometalated crystal structure sulfato

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Synthesis and Structure of an Enantiopure Dirhodium Loop with Unusual Axial Coordination

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Chinese Journal of Structural Chemistry 2011年第6期30卷 892-896页

作者：陈进余荣民 murillo Carlos A State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of Sciences Department of Chemistry Texas A&M University

The crystals of enantiopure SS-[cis-Rh2（Ph2C6H4）2（O2CC2F4CO2）]2（（CH3）2CHCH2NH2）3（1） were obtained from the reaction of S-[cis-Rh2（Ph2C6H4）2（CH3CN）6]BF4（S-2） and（Et4N）2（O2CC2F4CO2） in CH2Cl2/CH3OH under the presence of sec-butyl *** 1 crystallizes in orthorhombic,space group P212121 with a = 16.880（5）,b = 28.728（9）,c = 20.475（6） ,V = 9929（5） 3,Z = 4,C95H96Cl5F8N3O8.50P4Rh4,Mr = 2280.52,Dc = 1.526 g/cm3,F（000） = 4608 and μ（MoKα） = 0.922 *** final R = 0.0488 and wR = 0.1164 for 17204 observed reflections with I 〉2σ（I） and R = 0.0814 and wR = 0.1374 for all data with absolute structure parameter =-0.04（3）.Compound 1 contains two inherently chiral S-[cis-Rh2（Ph2C6H4）2] moieties which are connected by two（O2CC2F4CO2） dicarboxylate ligands in the equatorial *** of the dirhodium units with Rh-Rh distance of 2.5445（8）  is further coordinated by a sec-butyl amine in each axial *** dirohdium unit has only one axial sec-butyl amine ligand,and its Rh-Rh distance is 2.5079（9） .

关键词： enantiopure chiral dirhodium orthometalated crystal structure

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Random noise stimulation in the treatment of patients with neurological disorders

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Neural Regeneration Research 2022年第12期17卷 2557-2562页

作者： Mateo A.Herrera-murillo Mario Treviño Elias Manjarrez Facultad de Medicina Plan de Estudios Combinados en Medicina(PECEM)UNAMCircuito InteriorCiudad UniversitariaAv.UniversidadCiudad de MéxicoMéxico Instituto de Neurociencias Universidad de GuadalajaraGuadalajaraJaliscoMéxico Instituto de Fisiología Benemérita Universidad Autónoma de PueblaPueblaMéxico

Random noise stimulation technique involves applying any form of energy(for instance,light,mechanical,electrical,sound)with unpredictable intensities through time to the brain or sensory receptors to enhance sensory,motor,or cognitive *** noise stimulation initially employed mechanical noise in auditory and cutaneous stimuli,but electrical energies applied to the brain or the skin are becoming more frequent,with a series of clinical ***,recent evidence shows that transcranial random noise stimulation can increase corticospinal excitability,improve cognitive/motor performance,and produce beneficial aftereffects at the behavioral and psychological ***,we present a narrative review about the potential uses of random noise stimulation to treat neurological disorders,including attention deficit hyperactivity disorder,schizophrenia,amblyopia,myopia,tinnitus,multiple sclerosis,post-stroke,vestibular-postural disorders,and sensitivity *** of the reviewed studies reveal that the optimal way to deliver random noise stimulation-based therapies is with the concomitant use of neurological and neuropsychological assessments to validate the beneficial *** addition,we highlight the requirement of more randomized controlled trials and more physiological studies of random noise stimulation to discover another optimal way to perform the random noise stimulation interventions.

关键词： auditory noise mechanical noise neurological disorders neuronal noise noise galvanic vestibular stimulation non-invasive brain stimulation transcranial electrical stimulation transcranial random noise stimulation

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