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Algebra Colloquium 2021年第1期28卷 87-90页

作者： oscar guajardo garza Marina Rasskazova Liudmila Sabinina Centro de Investigacion en Ciencias UAEMCuernavacaMexico Omsk State Technical University pr.Mira 11OmskRussia

We study the variety of binary Lie algebras defined by the identities x^(2)=J(x,y,zu)=0,where J(a,b,c)denotes the Jacobian of a,b,*** on previous work by Carrillo,Rasskazova,Sabinina and Grishkov,in the present articl... 详细信息

关键词： Malcev theorem Levi factor splitting algebra binary Lie algebra

Mapping aboveground biomass by integrating geospatial and forest inventory data through a k-nearest neighbor strategy in North Central Mexico

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Journal of Arid Land 2014年第1期6卷 80-96页

作者： Carlos A AGUIRRE-SALADO Eduardo J TREVIO-garza oscar A AGUIRRE-CALDERóN Javier JIMNEZ-PREZ Marco A GONZLEZ-TAGLE José R VALDZ-LAZALDE Guillermo SNCHEZ-DíAZ Reija HAAPANEN Alejandro I AGUIRRE-SALADO Liliana MIRANDA-ARAGóN Faculty of Forest Sciences Autonomous University of Nuevo Leon Faculty of Engineering Autonomous University of San Luis Potosi Forestry Program Postgraduate College Haapanen Forest Consulting Faculty of Agronomy and Veterinary Autonomous University of San Luis Potosí

As climate change negotiations progress,monitoring biomass and carbon stocks is becoming an important part of the current forest ***,national governments are interested in developing forest-monitoring strategies using geospatial *** statistical methods for mapping biomass,there is a nonparametric approach called k-nearest neighbor(kNN).We compared four variations of distance metrics of the kNN for the spatially-explicit estimation of aboveground biomass in a portion of the Mexican north border of the intertropical *** derived,climatic,and topographic predictor variables were combined with the Mexican National Forest Inventory(NFI)data to accomplish the *** of distance metrics applied into the kNN algorithm was evaluated using a cross validation leave-one-out *** results indicate that the Most Similar Neighbor(MSN)approach maximizes the correlation between predictor and response variables(r=0.9).Our results are in agreement with those reported in the *** findings confirm the predictive potential of the MSN approach for mapping forest variables at pixel level under the policy of Reducing Emission from Deforestation and Forest Degradation(REDD+).

关键词： k-nearest neighbor Mahalanobis most similar neighbor MODIS BRDF-adjusted reflectance forest inventory the policy of Reducing Emission from Deforestation and Forest Degradation

Genetic Diversity of the Endemic Xantus’ Hummingbird Using 16 Novel Polymorphic Microsatellite Loci, and Their Cross Amplification between Six Related Species

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Open Journal of Genetics 2016年第1期6卷 19-27页

作者： Cristina González-Rubio Sanvicente Ricardo Rodríguez-Estrella oscar Adrián Lozano-garza Francisco J. García-De-León Laboratorio de Genética para la Conservación Centro de Investigaciones Biológicas del Noroeste La Paz Mexico Laboratorio de Análisis Espacial Ecología y Conservación Centro de Investigaciones Biológicas del Noroeste La Paz Mexico

A set of 16 microsatellite loci was developed and characterized for the Xantus’ hummingbird (Hylocharis xantusii) by using 454 next-generation sequencing. Twenty-five H. xantusii samples from one population were genotyped;all loci were polymorphic, with the number of alleles ranging from three to ten. The mean observed heterozygosity was 0.681 for all loci. No significant linkage disequilibrium was detected, but five loci (Hxan05, 06, 09, 13 and 14) showed deviation from Hardy-Weinberg equilibrium. These microsatellite loci are the first to be characterized for H. xantusii. A moderate to high level of cross-species amplification was observed across the six hummingbird species (31% - 87.5%), with the best cross amplification results observed in the closest related species (H. leucotis, Cynanthus latirostris, Calypte costae). The availability of these molecular tools allows assessing questions integrating population genetics, ecology, conservation, and evolutionary history for H. xantusii and for other phyogenetically related species.

关键词： Baja California Peninsula Hylocharis xantusii Microsatellites Pyrosequencing Cross-Species Amplification

Output feedback adaptive super twisting sliding mode control for quadrotor UAVs

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Control Theory and Technology 2024年第1期22卷 92-105页

作者： oscar Salas-Peña Jesus DeLeón-Morales Susana V.Gutiérrez-Martínez École Centrale de Nantes-LS2N UMR 6004 CNRS44300NantesFrance Facultad de Ingeniería Mecánica y Eléctrica Universidad Autónoma de Nuevo León66451San Nicolás de Los GarzaMexico

In this paper, a sliding mode control with adaptive gain combined with a high-order sliding mode observer to solve the tracking problem for a quadrotor UAV is addressed, in presence of bounded external disturbances and parametric uncertainties. The high order sliding mode observer is designed for estimating the linear and angular speed in order to implement the proposed scheme. Furthermore, a Lyapunov function is introduced to design the controller with the adaptation law, whereas an analysis of finite time convergence towards to zero is provided, where sufficient conditions are obtained. Regarding previous works from literature, one important advantage of proposed strategy is that the gains of control are parameterized in terms of only one adaptive parameter, which reduces the control effort by avoiding gain overestimation. Numerical simulations for tracking control of the quadrotor are given to show the performance of proposed adaptive control–observer scheme.

关键词： Adaptive super twisting controller High-order sliding modes observer UAV

New Interpretations about Clonal Architecture for the Sour Pitaya (Stenocereus gummosus, Cactaceae), Arising from Microsatellite Markers of de novoIsolation and Characterization

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Open Journal of Genetics 2015年第1期5卷 1-11页

作者： oscar Adrián Lozano garza José L. León de la Luz Susana Favela Lara Francisco J. García de León Laboratorio de Genética para la Conservación Centro de Investigaciones Biológicas del Noroeste La Paz Mexico Departamento de Ecología Facultad de Ciencias Biológicas Universidad Autónoma de Nuevo LeónSan Nicolás de los Garza Mexico

The use of molecular markers has improved the ecological and evolutionary research in the case of clonal reproduction species, allowing the identification of boundaries among clonal modules (ramets), genetic individuals (genets), and populations. Microsatellite markers were developed for Stenocereus gummosus, a columnar cactus with both sexual and clonal reproduction which is distributed in the Sonoran Desert, Mexico. 454-Pyrosequencing reads were analyzed to detect microsatellite markers. Forty primer pairs were screened to look for polymorphism. Nine loci were genotyped for two S. gummosus localities. Sampling strategy was intended to avoid collecting a genetic individual more than once, considering that clonal architecture for this cactus was previously deduced as clumped. Polymorphic loci exhibited low allele count, ranging from 2 - 7 (mean of 3.78 ± 0.62 SE);mean heterozygosity values were 0.221 and 0.234 HO and 0.408 and 0.306 HE, with FIS of 0.383 and 0.299, for peninsular and continental localities respectively. Unexpectedly, some multilocus genotypes were found repeated within locality, which were assumed as clones since data was evaluated as sufficient (clonal richness R of 0.966 and 0.897). These results were different from those previously reported: the distribution of clones might as well be intermingled, having a minimum ramet dispersion distance of 30 m. This characteristic was also consistent with the recent colonization proposed for this and other arid lands plants. A wider genetic neighborhood, due to clone dispersion might affect diversity indexes while increasing the chance of geitonogamy and mating among relatives. The markers isolation and its population characterization allowed addressing new questions about S. gummosus ecology, clonal reproduction and reproductive biology.

关键词： Cactaceae Clonal Architecture Microsatellites Pyrosequencing Stenocereus

Construction of aboveground biomass models with remote sensing technology in the intertropical zone in Mexico

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Journal of Geographical Sciences 2012年第4期22卷 669-680页

作者： AGUIRRE-SALADO Carlos Arturo TREVINO-garza Eduardo Javier AGUIRRE-CALDERON oscar Alberto JIMENEZ-PiEREZ Javier GONZALEZ-TAGLE Marco Aurelio VALDEZ-LAZALDE Jose Rene M IRANDA-ARAGON Liliana AGUIRRE-SALADO Alejandro lvan Autonomous University of Nuevo Leon Linares NL 67700 Mexico Autonomous University of San Luis Potosi SLP 78290 Mexico The College of Postgraduates Texcoco MEX 56230 Mexico

Spatially-explicit estimation of aboveground biomass （AGB） plays an important role to generate action policies focused in climate change mitigation, since carbon （C） retained in the biomass is vital for regulating Earth＇s temperature. This work estimates AGB using both chlorophyll （red, near infrared） and moisture （middle infrared） based normalized vegetation indices constructed with MCD43A4 MODerate-resolution Imaging Spectroradiometer （MODIS） and MOD44B vegetation continuous fields （VCF） data. The study area is located in San Luis Potosi, Mexico, a region that comprises a part of the upper limit of the intertropical zone. AGB estimations were made using both individual tree data from the National Forest Inventory of Mexico and allometric equations reported in scientific literature. Linear and nonlinear （expo- nential） models were fitted to find their predictive potential when using satellite spectral data as explanatory variables. Highly-significant correlations （p = 0.01 ） were found between all the explaining variables tested. NDVI62, linked to chlorophyll content and moisture stress, showed the highest correlation. The best model （nonlinear） showed an index of fit （Pseudo - r2） equal to 0.77 and a root mean square error equal to 26.00 Mg/ha using NDVI62 and VCF as explanatory variables. Validation correlation coefficients were similar for both models： linear （r = 0.87＊＊） and nonlinear （r = 0.86＊＊）.

关键词： MODIS MCD43A4 MOD44B forest inventory regression

The effect of electrical current on lubricant film thickness in boundary and mixed lubrication contacts measured with ultrasound

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Friction 2024年第8期12卷 1882-1896页

作者： Julio A.CAO-ROMERO-GALLEGOS Saeid TAGHIZADEH oscar A.AGUILAR-ROSAS R.S.DWYER-JOYCE Leonardo I.FARFAN-CABRERA Tecnologico de Monterrey Escuela de Ingeniería y CienciasAve.Eugenio Garza Sada 2501MonterreyN.L.64849México Department of Mechanical Engineering Leonardo Centre for TribologyUniversity of SheffieldSheffield S13JDUK

This work explores experimentally the effects of DC electrical currents on lubricant film thickness alteration in lubricated sliding steel contacts in the boundary and mixed regime as measured by *** experiments were performed in a two-electrode cell-based pin-on-disk tester instrumented with ultrasonic *** and electrified tribological tests were conducted on steel flat-on-flat contacts under various speeds and loads using both a mineral base oil and a gear *** thickness,coefficient of friction(CoF),and electrical contact resistance(ECR)were measured during short experiments(30 s)in unelectrified and electrified(1.5 and 3 A)*** results suggest that film thickness,CoF,and all ECR are altered by passing DC currents through the *** particular,film thickness increased and decreased,respectively,by applying electricity at the different speeds and loads *** alterations were majorly ascribed to oil viscosity decrease by local heat and surface oxidation caused by electrical discharge and break down at the interface.

关键词： electrified sliding ultrasonic measurement electric vehicles pin-on-disk

Isolation and Characterization of 26 Microsatellite Loci for the Shortfin Silverside Fish Chirostoma humboldtianumValenciennes1835 (Atherinopsidae: Menidiinae) Derived from Next Generation Sequencing and Their Cross-Amplification in Central Mexican Atherinopsids

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Open Journal of Genetics 2014年第5期4卷 355-361页

作者： Barriga-Sosa Irene de los Angeles Rosa María García-Martínez Jhoana Díaz-Larrea oscar Adrián Lozano garza Francisco Javier García-De-León Departamento de Hidrobiología Universidad Autónoma Metropolitana Iztapalapa México D.F. México Laboratorio de Genética y Biología Molecular Planta Experimental de Producción Acuícola Departamento de Hidrobiología Universidad Autónoma Metropolitana Iztapalapa México D.F. México Laboratorio de Genéticapara la Conservación Centro de Investigaciones Biológicas del Noroeste Instituto Politécnico Nacional La Paz México

The endemic silverside fish C. humboldtianum is of great ichtyologycal, economical and cultural relevance in central Mexico and it has been suggested that it is among a group of other “peces blancos”, the most ancestral species. Here we characterized a set of 26 microsatellite loci from the species in order to further assess population and phylogeographic issues that aid in evaluating their highly impacted populations. From 58 primer pairs tested on specimens from Villa Victoria dam (Rio Balsas Basin), 26 loci positively amplified on the species and cross-primed on specimens of the closely related and threatened Poblana alchichica, C. promelas and C. riojai. Loci resolved medium and high genetic variation (mean NA = 14.3, SD = 9.38;mean HO & HE = 0.47, SD = 0.32 and 0.58, SD = 0.32, respectively) and it is expected that these polymorphic loci are also useful in studing threatened atherinopsid species.

关键词： Endemic Polymorphism Villa Victoria Poblana alchichica C. promelas C. riojai