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journal of China University of Geosciences 2008年第1期19卷 85-92页

作者： j.a vargas-guzmán Saudi Aramco Dhahran 31311 KSA

An analysis of statistical expected values for transformations is performed in this study to quantify the effect of heterogeneity on spatial geological modeling and evaluations. Algebraic transformations are frequently applied to data from logging to allow for the modeling of geological properties. Transformations may be powers, products, and exponential operations which are commonly used in well-known relations （e.g., porosity-permeability transforms）. The results of this study show that correct computations must account for residual transformation terms which arise due to lack of independence among heterogeneous geological properties. In the case of an exponential porosity-permeability transform, the values may be positive. This proves that a simple exponential model back-transformed from linear regression underestimates permeability. In the case of transformations involving two or more properties, residual terms may represent the contribution of heterogeneous components which occur when properties vary together, regardless of a pair-wise linear independence. A consequence of power- and product-transform models is that regression equations within those transformations need corrections via residual cumulants. A generalization of this result is that transformations of multivariate spatial attributes require multiple-point random variable relations. This analysis provides practical solutions leading to a methodology for nonlinear modeling using correct back transformations in geology.

关键词： reservoir static model intrinsic permeability non-Gaussian nonlinear residual moment cumulant unbiased simulation parameter.

Potential role of lava lizards as pollinators across the Galápagos Islands

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Integrative Zoology 2020年第2期15卷 144-148页

作者： Sandra HERVÍAS-PAREjO Manuel nOGALES Beatriz guzmÁn María del Mar TRIGO jens MOLESEn Pablo vargas Ruben HELEnO Anna TRAVESET Global Change Research Group Mediterranean Institute for Advanced StudiesMallorcaBalearic IslandsSpain Island Ecology and Evolution Research Group Institute of Natural Products and AgrobiologyCanary IslandsSpain Royal Botanical Garden of Madrid MadridSpain Department of Plant Biology Málaga UniversityMálagaSpain Department of Bioscience Aarhus UniversityAarhusDenmark Centre for Functional Ecology Department of Life SciencesUniversity of CoimbraCoimbraPortugal

Lizards have been reported as important pollinators on several oceanic *** we evaluate the potential role of Galápagos lava lizards(Microlophus spp.)as pollinators across their *** 3 years,we sampled pollen transport by 9 lava lizard species on the 10 islands where they are present,including 7 single-island ***,only 25 of 296 individuals sampled(8.4%)transported pollen of 10 plant species,the most common being Prosopis juliflora,Exodeconus miersii,Sesuvium *** Cordia *** least 8 of these plant species were native,and none were confirmed as introduced to the *** the low overall proportion of individuals carrying pollen,this was observed in 7 of the nine lizard species,and on 8 of the ten main islands(Española,Fernandina,Floreana,Isabela,Marchena,Pinta,Santa Cruz and Santiago),suggesting that this is a widespread *** results reported here support the potential role of lava lizards as pollinators across their radiation,although they may represent a relatively modest contribution when compared with birds and ***,we cannot discard that lizards may be ecologically significant for particular plant species and ecosystems given the specific climatic condition and functional diversity of each island.

关键词： flower visitation Microlophus spp. mutualistic interactions pollination vertebrate radiation

near shore seismic movements induced by seaquakes using the boundary element method

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Earthquake Engineering and Engineering Vibration 2017年第3期16卷 571-585页

作者： Alejandro Rodríguez-Castellanos Manuel Carbajal-Romero norberto Flores-guzmán j.Efraín Rodríguez-Sánchez Andriy Kryvko instituto mexicano del petróleo eje central lázaro cárdenas 152Gustavo A.MaderoDistrito FederalMéxico escuela superior de ingeniería mecánicay eléctrica instituto politécnico nacionalupalmEdif.5Av.Instituto Politécnico Nacional S/NCol.LindavistaGustavo A.MaderoDistrito FederalMéxico escuela superior de ingeniería mecánicay eléctrica instituto politécnico nacionalunidad profesional azcapotzalcoDistrito FederalMéxico centro de investigación en matemáticas jalisco s/nmineral de valencianaguanajuatoMéxico

This study quantifies seismic amplifications in near-shore arising from seaquakes. Within the Boundary Element Method, boundary elements are used to irradiate waves and force densities obtained for each element. Huygens′ Principle is implemented since the diffracted waves are constructed at the boundary from which they are radiated, which is equivalent to Somigliana′s theorem. Application of boundary conditions leads to a system of integral equations of the Fredholm type of second kind and zero order. Several numerical configurations are analyzed： The first is used to verify the present formulation with ideal sea floor configurations to estimate seismic amplifications. With the formulation verified, simple slope configurations are studied to estimate spectra of seismic motions. It is found that P-waves can produce seismic amplifications from 1.2 to 3.9 times the amplitude of the incident wave. SV-waves can generate seismic amplifications up to 4.5 times the incident wave. Another relevant finding is that the highest amplifications are at the shore compared to the ones at the sea floor.

关键词： seismic amplifications seaquake earthquake elastic waves boundary element method near shore cities

Selection and Analysis of Polymorphisms in Somaclonal Variants of Agave americana Resistant to Fusarium oxysporum via an Ethyl Methanesulphonate Treatment

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Phyton-International journal of Experimental Botany 2021年第6期90卷 1727-1739页

作者： Sheila jazmín Reyes-Zambrano Carlos Alberto Lecona-guzmán Federico Antonio Gutiérrez-Miceli Víctor Manuel Ruiz-Valdiviezo Arely Anayansi vargas-Díaz Laboratorio de Biotecnología Vegetal Instituto Tecnológico de Tuxtla GutiérrezTecnológico Nacional de MéxicoTuxtla GutiérrezChiapas29050México COnACYT-Colegio de Postgraduados Campus Campeche ChampotónCampeche24450México

Agave americana *** were exposed to different concentrations of ethyl methanesulphonate(EMS)0,15,30,45 and 60 mM and to different times of exposure(2 and 4 h).The viability and capacity of shoot formation were shown to be affected when the callus were exposed to high concentrations(30–60 mM).Only the callus exposed to 15 mM EMS presented shoot formation;the exposure time of two hours produced the largest quantity of shoots regenerated per callus(21 shoots/callus).In order to generate somaclonal variants resistant to Fusarium oxysporum,a selection pressure was applied through of a culture filtrate(CF)of 100 ppm of the *** was made in callus obtained in the treatment with 15 mM EMS during 2 h of *** CF caused oxidation and necrosis in 71.25%of the callus;however,they were capable of generating shoots(3.5 shoots/callus).Molecular markers type RAPD,ISSR and DAMD were used to evaluate the genetic variation arising from the mutations caused by EMS on control plants and 16-month-old somaclonal *** polymorphic information content(PIC)for each one of the initiating groups was:0.28(DAMD),0.09(ISSR)and 0.14(RAPD).DAMD revealed a greater percentage of polymorphism than RAPD and *** bands were detected in the somaclonal *** indicated that the EMS caused genetic variation in the regenerated plants conferring resistance to them against Fusarium oxysporum.

关键词： Mutagenesis polymorphisms genetic variation molecular markers

Spatial variability of soil organic carbon stock in an olive orchard at catchment scale in Southern Spain

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International Soil and Water Conservation Research 2023年第2期11卷 311-326页

作者： jose A.Gòmez Gema guzmán Tom Vanwalleghem Karl Vanderlinden Institute for Sustainable Agriculture.Spanish national Research Council(IAS-CSIC) Alameda del Obispo S/N14004CordobaSpain Department of Agronomy University of CordobaCampus de Rabanales14071CordobaSpain Centro IFAPA Alameda del Obispo 14004CordobaSpain

Orchards have a high potential for carbon ***,little research is available on the spatial variability at catchment scale and on the difference between the tree area and the *** analyzed theik spatial variability of soil organic carbon stock,SOCstock at 90 cm depth in an 8-ha catchment in Southern Spain with olives on a vertic *** showed higher soil organic carbon concentration,SOC,in the tree area as compared to the lane up to 60 cm depth,but its impact on SOCstock was negligible since it was compensated by the higher soil bulk density in the *** at different depths was correlated with that in the top 0-5 *** overall SOCstock of the orchard was 4.14 kg m^(-2),ranging between 1.8 and 6.0 kg m^(-2).This SOCstock is in the mid-lower range of values reported for olive orchards,measured at smaller scale,and similar to those other intensive field crops and agroforestry under comparable rainfall *** spatial variability in SOCstock was correlated to several geomorphological variables:elevation,cumulative upstream area,topographic wetness index,sediment transport index,and tillage *** in SOC and SOCstock are driven by the sediment redis-tribution downslope,mainly by tillage erosion,and higher soil water availability in lower areas allowing higher biomass *** topographic indexes and the correlation between SOC in the topsoil and SOCstock up to 90 cm should be further explored in other typology of olive orchards for facilitating the mapping of SOC_(stock).

关键词： Carbon sequestration Mediterraneancrops Catchment Spatial variability Vertic soils

Total Phenols,Flavonoids and Antioxidant Activity in Annona muricata and Annona purpurea Callus Culture

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Phyton-International journal of Experimental Botany 2019年第2期88卷 139-147页

作者： M.Y.Ovando-Domínguez M.C.Luján-Hidalgo D.González-Mendoza A.A.vargas-Díaz n.Ruiz-Lau F.A.Gutiérrez-Miceli C.A.Lecona-guzmán Laboratorio de Cultivo de Tejidos Vegetales.Tecnológico nacional de México/Instituto Tecnológico de Tuxtla Gutiérrez Carretera Panamericana Km.1080.Tuxtla GutiérrezChiapasC.P.29050México Instituto de Ciencias Agrícolas de la Universidad Autónoma de Baja California(ICA-UABC).Carretera a Delta s/n C.P.21705 Ejido Nuevo LeónBaja CaliforniaMéxico COnACYT-Colegio de Postgraduados Campus CampecheCarretera Federal Haltunchén-Edzna km 17.5.SihochacChampotónCampecheCP 24450México COnACYT-Tecnológico nacional de México/Instituto Tecnológico de Tuxtla Gutiérrez.Carretera Panamericana Km.1080.Tuxtla Gutiérrez ChiapasC.P.03940México

Callus cultures of Annona muricata and Annona purpurea were induced in Murashige and Skoog(MS)medium supplemented with different concentrations of 1-naphthylacetic acid(nAA),6-benzyladenine(BA)and 2,4-dichlorophenoxyacetic acid(2,4-D)utilized hypocotyls with *** highest percentage of callus formation was the treatment supplemented with 3 mg L-1 nAA for ***(100%)while for *** in lower percentage(75%).BA stimulated the formation of shoots in all the evaluated concentrations,being the concentration of 2 mg L-1 the one that induced the greater formation of shoots for ***(23 shoots/explant)and ***(28 shoots/explant).The content of total phenols,flavonoids and antioxidant activity was measured in the callus obtained from both *** results showed that a higher content of total phenols was quantified in callus of ***(27.8 mg g-1 dw)compared to ***(23.2 mg g-1 dw).The highest content of total flavonoids was observed in the callus of ***(8.0μg g-1 dw).Antioxidant activity was determined by the 2,2-diphenyl-1-picrylhydracil radical *** concentration required for 50%inhibition(IC50)of the 2,2-diphenyl-1-picrylhydracil radicals were 4.22μg mL-1 in methanolic extracts of callus of ***,while in extracts of callus of *** was 2.86μg mL-1,in both cases was greater than that found for *** culture of the species studied in this work represents an alternative for the production of natural antioxidants.

关键词： Annonaceae antioxidant activity 6-benzyladenine secondary metabolites tissue culture

Effect of airflow on biodrying of gardening wastes in reactors

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journal of Environmental Sciences 2013年第5期25卷 865-872页

作者： F.j.Colomer-Mendoza L.Herrera-Prats F.Robles-Martínez A.Gallardo-Izquierdo A.B.Pia-guzmn Department of Mechanical Engineering and Construction (Universidad Jaume I)Jaume 1st University.Ave.Sos Baynat s/nCastellón 12071Spain Biotechnology Multidisciplinary Professional Unit (Instituto Politcnico Nacional)National Politechnic Institute.Ave.Acueduct of Guadalupe s/n Barrio la Laguna TicomnGustavo A.Madero 07340Mxico DF.Mxico

Biodrying consists of reducing moisture by using the heat from aerobic *** parameters that control the process are：aeration,temperature during the process,initial moisture of biowaste,and temperature and relative humidity of the input *** mowing and garden waste from the gardens of the University jaume I,Castellón（Spain）were used as a *** was performed in 10 reactors with known air volumes from 0.88 to 6.42 L/（min·kg dry weight）.To promote aeration,5 of the reactors had 15% of a bulking agent *** experiment lasted 20 *** the experiments it was found that the bulking agent led to greater weight ***,the increased airflow rate was not linearly proportional to the weight loss.

关键词： biodrying biowaste stabilization aerobic fermentation bulking agent

Appraising trapping efficiency of vegetative barriers in agricultural landscapes:Strategy based on a probabilistic approach based on a review of available information

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International Soil and Water Conservation Research 2024年第3期12卷 615-634页

作者： josé-Antonio Muñoz Gema guzmán María-Auxiliadora Soriano josé A.Gómez Institute for Sustainable Agriculture(IAS)-CSIC Cordoba14004Spain Andalusian Institute of Agricultural and Fisheries Research and Training(IFAPA) Granada18004Spain Agronomy Department(DAUCO) University of CordobaCordoba14071Spain

Vegetative barriers have proven their effectiveness in controlling water erosion and enhancing other ecosystem services in agricultural *** characteristic has led to the conservation and promotion of vegetative barriers as landscape elements by the Common Agricultural Policy and other policy *** reviews have dealt with the trapping efficiency of vegetated barriers,although they usually focus on studies from humid climates where their implantation and survival are more ***,vegetated barriers are also an attractive alternative in arid and semi-arid *** limit competition for water and nutrients with crops to a reduced area compared to other best management practices,such as cover *** study presents a review of trapping efficiency of sediment,runoff,and nutrients(P and n)by vegetative barriers in regions of humid and arid,and semi-arid,climates,and a strategy based on sediment trapping efficiency probability,which in turn is based on the results obtained from our *** types of independent variables were grouped and identified for the review:related to the vegetative barrier dimension(buffer width,slope of the plot,and buffer area ratio),and related to the experimental conditions(type of vegetation in the buffer,soil protection of the non-buffered area,type of climate,type of experimental measurement and origin of rainfall).An explor-atory analysis evaluated the significance of the experimental variables,which identified the need to focus on experiments under natural rainfall since those carried out with simulated rainfall presented statis-tically significant *** general,average trapping efficiencies for runoff and sediment were 40.1 and 62.6%,*** nutrients,values of trapping efficiencies had an average of 44.9%for phosphorus and 38.4%for *** and sediment trapping efficiency in arid and semi-arid re-gions tended to be higher than in humid *** dimensional

关键词： Connectivity Sediment transport Runoff nutrients Experimental plots Buffer strip

Relative toxicity of three wheat herbicides to two species of Coccinellidae

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Insect Science 2010年第5期17卷 434-438页

作者： j. P. Michaud German vargas Department of Entomology Kansas State University Hays Kansas USA

On the High Plains of the USA, herbicides specific for broad-leaf weeds are regularly applied to winter wheat in the early spring, sometimes late enough to coincide with the colonization of fields by cereal aphids and their natural enemies. We tested the toxicity of three such herbicides, Ally （Dupont）, Rave （Syngenta） and 2,4-D ester （generic）, to neonate larvae of two coccinellid species important in cereal aphid biocontrol, Coleomegilla maculata DeGeer and Hippodamia convergens Gurrin-Mrneville. Topical treatment of larvae with 2,4-D resulted in 25% and 60% mortality in the two species, respectively, with surviving C. maculata larvae experiencing a 5% increase in developmental time. no significant effects were noted for the other two materials, save for a 2.5% increase in developmental time for C. maculata larvae exposed to Rave. no material caused significant mortality in either species when larvae were fed on prey （Schizaphis graminum Rondani） treated with herbicide 24 h earlier, although 2,4-D reduced developmental time slightly in C. maculata. When herbicide applications are delayed enough in spring to coincide with aphid activity in wheat, farmers can reduce the risk of disrupting biological control by selecting an alternative to 2,4-D.

关键词： 2,4-D Coleomegilla maculata dicamba Hippodamia convergens Schizaphis graminum thifensulfuron methyl

Adult intussusception secondary to an ileum hamartoma

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World journal of Gastrointestinal Oncology 2011年第6期3卷 103-106页

作者： Carlos M nuo-guzmán josé Arróniz-jáuregui Ismael Espejo josué Solís-Ugalde josé Ignacio Gómez-Ontiveros Arturo vargas-Gerónimo jesús Valle-González Department of General Surgery Antiguo Hospital Civil de Guadalajara "Fray Antonio Alcalde"Calle Hospital No.278Sector Hidalgo.C.P.44280GuadalajaraJaliscoMexico Department of Histopathology Antiguo Hospital Civil de Guadalajara "Fray Antonio Alcalde"Calle Hospital No.278Sector Hidalgo.C.P.44280 GuadalajaraJaliscoMexico Department of Radiology Antiguo Hospital Civil de Guadalajara "Fray Antonio Alcalde"Calle Hospital No.278Sector Hidalgo.C.P.44280GuadalajaraJaliscoMexico

Intussusception is a rare condition in the adult ***,in contrast to its presentation in children,an identifiable etiology is found in the majority of *** manifestations of adult intussusception are non-specific and patients may present with acute,intermittent or chronic symptoms,predominantly those of intestinal obstruction.A 27-year-old male patient with recurrent abdominal pain secondary to intussusception is herein *** clinical presentation and ultrasonographic findings led to the *** laparotomy,an ileal hamartoma was found as the lead point of the *** management and histopathologic studies are described.A recurrent intestinal obstruction and classic ultrasound findings may lead to the diagnosis of intussusception but surgical exploration remains *** principle of resection without reduction is well established.

关键词： Adult intussusception Ileum hamartoma Intestinal obstruction