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Effect of Multipoint Heterogeneity on nonlinear Transformations for Geological Modeling: Porosity-Permeability Relations Revisited

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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.

DnA repair deficiency in neuropathogenesis:when all roads lead to mitochondria

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Translational neurodegeneration 2019年第1期8卷 157-170页

作者： Luis Bermúdez-guzmán Alejandro Leal Section of Genetics and Biotechnology School of BiologyUniversidad de Costa RicaSan José11501Costa Rica neuroscience Research Center Universidad de Costa RicaSan JoséCosta Rica

Mutations in DnA repair enzymes can cause two neurological clinical manifestations:a developmental impairment and a degenerative *** kinase 3′-phosphatase(PnKP)is an enzyme that is actively involved in DnA repair in both single and double strand break repair *** in this protein or others in the same pathway are responsible for a complex group of diseases with a broad clinical ***,mitochondrial dysfunction also has been consolidated as a hallmark of brain *** we provide evidence that supports a shared role between mitochondrial dysfunction and DnA repair defects in the pathogenesis of the nervous *** models,we analyze PnKP-related disorders,focusing on Charcot-Marie-Tooth disease and ataxia.A better understanding of the molecular dynamics of this relationship could provide improved diagnosis and treatment for neurological diseases.

关键词： DnA repair Mitochondrial dysfunction neurodegeneration Ataxia PnKP

Endophytes versus biotrophic and necrotrophic pathogens—are fungal lifestyles evolutionarily stable traits?

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Fungal Diversity 2013年第3期60卷 125-135页

作者： Luis Delaye Graciela García-guzmán Martin Heil Departamento de Ingeniería Genética Centro de Investigación y de Estudios Avanzados(CINVESTAV)IrapuatoGuanajuatoMexico Departamento de Ecología Evolutiva Instituto de EcologíaUNAMMéxico CityMexico

Endophytes infect living plant tissues without causing symptoms of ***,many of them contribute to the resistance phenotype of their ***,fungal endophytes are generally closely related to plant pathogens,fungi that either develop within living host tissue(biotrophic fungi)or that kill the host cells and then live in the dead tissue(necrotrophic fungi).We adopted a phylogenetic approach to investigate whether these strategies represent evolutionarily stable lifestyles and to elucidate their general phylogenetic *** analysed 163 fungal strains for which we found information on the sequence of the 5.8S rRnA gene and the flanking internal transcribed spacer regions,the identity of the host plant and the concrete phenotypic outcome of the infection.A Maximum-Likelihood analysis combined with ancestral character mapping by maximum parsimony revealed that some fungal lineages had switched multiple times between a necrotrophic and an endophytic *** character mapping indicated a minimum of four changes from an endophytic to a necrotrophic lifestyle,four changes in the opposite direction and eight changes among these lifestyles for which the direction could not be determined *** contrast,biotrophs formed five clusters that did not contain necrotrophs or *** biotrophy evolves there is apparently no regression to one of the other two *** conclude that biotrophy usually represents a derived and evolutionarily stable trait,whereas fungi easily can switch between an endophytic and necrotrophic lifestyle at the evolutionary and even the ecological *** experimental studies should focus on the environmental or genetic changes that cause the rapid switches between these two phenotypically different lifestyles.

关键词： Disease expression Fungi Plant pathogens Phylogenetic effects

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

Factors affecting populations of the endemic Iberian hare(Lepus granatensis)after the first myxomatosis outbreaks in Central Spain

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Integrative Zoology 2023年第6期18卷 981-993页

作者： Carlos LÁZARO JoséLuis guzmÁn Fabián CASAS Carlos SÁnCHEZ-GARCÍA Department of Research Fundación ArtemisanCiudad RealSpain Department of Zoology Faculty of SciencesUniversity of GranadaGranadaSpain

The Iberian hare(Lepus granatensis)is an endemic species distributed in Spain and *** outbreaks affecting this species were detected in 2018 in Central and Southern Spain,spreading *** to evaluate factors affecting the status of hare population after the arrival of myxomatosis,we conducted 108 nocturnal hare counts in Central Spain during two study periods(winter/spring and summer/autumn)in 54 different hunting grounds,covering 1071 km and observing 884 *** mean density in winter/spring was 7.66 hares/100 ha,(range 6.14-9.54/100 ha),while in summer/autumn,it was 3.4 hares/100 ha(range 2.6-4.4/100 ha).Densities of hares were not affected by the dominant habitat and the presence/absence of myxomatosis *** were more abundant at hunting grounds at a higher altitude and in those conducting targeted management,while detection of myxomatosis was related to lower altitude and higher levels of game management.A MaxEnt model used to generate a risk map for myxomatosis occurrence showed that the temperature annual range was the most important predictor,which suggests that environmental factors affecting myxomatosis vectors(mosquitoes,fleas,and ticks)could play a key role in disease *** myxomatosis in hares is becoming endemic,hare densities may be improved by game management and the monitoring and surveillance of this emerging *** surveillance programs could be the basis of effective collaborations between hunters,researchers,and environmental managers.

关键词： game management habitat Iberian hare MaxEnt monitoring myxomatosis

Entanglement beating in free space through spin–orbit coupling

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Light(Science & Applications) 2018年第1期7卷 1040-1046页

作者： Eileen Otte Carmelo Rosales-guzmán Bienvenu ndagano Cornelia Denz Andrew Forbes Institute of Applied Physics University of MuensterMuenster D-48149Germany School of Physics University of the WitwatersrandWits 2050South Africa

It is well known that the entanglement of a quantum state is invariant under local unitary *** rule dictates,for example,that the entanglement of internal degrees of freedom of a photon remains invariant during free-space ***,we outline a scenario in which this paradigm does not *** local Bell states engineered from classical vector vortex beams with non-separable degrees of freedom,the so-called classically entangled states,we demonstrate that the entanglement evolves during propagation,oscillating between maximally entangled(purely vector)and product states(purely scalar).We outline the spin–orbit interaction behind these novel propagation dynamics and confirm the results experimentally,demonstrating spin–orbit coupling in paraxial *** demonstration highlights a hitherto unnoticed property of classical entanglement and simultaneously offers a device for the on-demand delivery of vector states to targets,for example,for dynamic laser materials processing,switchable resolution within stimulated emission depletion(STED)systems,and a tractor beam for entanglement.

关键词： classical entanglement complex light fields entanglement oscillation spin-orbit coupling

Post-testing measurement of freely movable and diffusible hydrogen in context of WEC formation at cylindrical roller thrust bearings from 100Cr6

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Friction 2021年第4期9卷 876-890页

作者： Martin LInZMAYER Francisco GUTIÉRREZ guzmÁn Gregor MAnKE Georg JACOBS Christopher SOUS Michael POHL Institute for Machine Elements and System Engineering RWTH Aachen UniversitySchinkelstrasse 10Aachen 52062Germany Institute for Materials Material TestingRuhr University BochumUniversitatsstr 150Bochum 44801Germany

Sub-surface crack networks in areas of altered microstructure are a common cause for bearing *** to its appearance under light microscopy,the damage pattern is referred to as White Etching Cracks(WEC).The root causes leading to the formation of WEC are still under ***,it has already been shown that atomic hydrogen can have an accelerating effect on the formation and propagation of *** addition to hydrogen pre-charging,hydrogen can be released and absorbed during rolling/sliding due to the decomposing of the lubricant and *** current work focuses on the analysis of the hydrogen content of cylindrical roller thrust bearings after testing in a FE8 type test rig using two different *** the framework of this work,two different hydrogen analysis methods were used and assessed regarding their *** results show that the so-called Hydrogen Collecting Analysis(HCA)is more suitable to investigate the correlation between lubricant chemistry and hydrogen content in the test bearings than the Local Hydrogen Analysis(LHA).The measurements with the HCA show a continuously increasing freely movable and diffusible hydrogen content under tribological conditions,which leads to the formation of *** tests with an oil without hydrogen showed that the tendency of the system to fail as a result of WEC can be reduced by using a lubricant without hydride compounds.

关键词： White Etching Crack(WEC) White Etching Areas(WEA) hydrogen content Hydrogen Collecting Analysis(HCA) freely movable hydrogen diffusible hydrogen cylindrical roller thrust bearing roller bearings roller contact fatigue

Methanogenesis and Methanotrophy in Soil: A Review

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Pedosphere 2014年第3期24卷 291-307页

作者： n.SERRAnO-SILVA Y.SARRIA-guzmn L.DEnDOOVEn M.LUnA-GUIDO Laboratory of Soil Ecology ABACUS Cinvestav Instituto Politecnico Nacional 2508 C.P.07360 mexico d.f.(mexico)

Global warming, as a result of an increase in the mean temperature of the planet, might lead to catastrophic events for humanity. This temperature increase is mainly the result of an increase in the atmospheric greenhouse gases （GHG） concentration. Water vapor, carbon dioxide （CO2）, methane （CH4） and nitrous oxide （n20） are the most important GHG, and human activities, such as industry, livestock and agriculture, contribute to the production of these gases. Methane, at an atmospheric concentration of 1.7 gmol tool-1 currently, is responsible for 16% of the global warming due to its relatively high global warming potential. Soils play an important role in the CH4 cycle as methanotrophy （oxidation of CH4） and methanogenesis （production of CH4） take place in them. Understanding methanogenesis and methanotrophy is essential to establish new agriculture techniques and industrial processes that contribute to a better balance of GHG. The current knowledge of methanogenesis and methanotrophy in soils, anaerobic CH4 oxidation and methanotrophy in extreme environments is also discussed.

关键词： anaerobic CH4 oxidation biological production global warming methanogenic archaea methanotrophic bacteria

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