The Benito Juárez Autonomous University of Oaxaca is a public university located in the city of Oaxaca de Juárez in state of Oaxaca, Mexico.The University was founded on January 8, 1827 as the Oaxacan Institute for Arts and science. Initially courses were offered in Medicine, Surgery, Civil and Natural Law, Public Law, Canon Law and Ecclesiastical History, Political Economy, Statistics, Geography and Physics, Mathematics logic, ethics, English, and French. Wikipedia.
Luna-Vega I.,National Autonomous University of Mexico |
Espinosa D.,National Autonomous University of Mexico |
Rivas G.,National Autonomous University of Mexico |
Contreras-Medina R.,Benito Juarez Autonomous University of Oaxaca
Systematics and Biodiversity | Year: 2013
Mexico is considered a megadiverse country containing more than 10% of the world's biodiversity. The distribution of this species richness and endemism is different among the different Mexican states. We examined the species richness patterns of 13 families of vascular plants (including ferns, gymnosperms and angiosperms) in Mexico using political divisions (states) as units of analysis. We analysed the species richness values (absolute richness, endemic richness and restrictive richness) of these plant families using stepwise multiple regression analysis, assessing their relationship with a set of 10 environmental variables (expressed as heterogeneity coefficients). A combined cluster analysis with multidimensional scaling analysis (MDS) and an analysis of similarities were also undertaken to define the spatial-geographical patterns. Additionally, we proposed a methodological strategy to determine which states of Mexico have priorities for conservation. Our results suggested that the three species richness values used were significantly predicted by environmental factors, especially by climatic heterogeneity. Notwithstanding that a linear pattern was recognized, the Mexican states were gathered in four groups, which were confirmed by the MDS and the cluster analysis: (1) the Yucatan Peninsula, (2) arid Mexico, (3) the Mexican Transition Zone and (4) the megadiverse states. We proposed that 12 Mexican states include all the environmental conditions and are candidates for developing conservation programmes: (1) Quintana Roo, Tabasco and Yucatán, (2) Baja California, Chihuahua and Sinaloa, (3) Guerrero, Jalisco and Nuevo León and (4) Chiapas, Oaxaca and Veracruz. © 2013 Taylor & Francis Group, LLC.
Escalante A.,Autonomous University of Puebla |
Carbajal L.,Benito Juarez Autonomous University of Oaxaca
Annals of Physics | Year: 2011
The Hamiltonian analysis for the Chern-Simons theory and Pontryagin invariant, which depends of a connection valued in the Lie algebra of SO(3,. 1), is performed. By applying a pure Dirac's method we find for both theories the extended Hamiltonian, the extended action, the constraint algebra, the gauge transformations and we carry out the counting of degrees of freedom. From the results obtained in the present analysis, we will conclude that the theories under study have a closed relation among its constraints and defines a topological field theory. In addition, we extends the configuration space for the Pontryagin theory and we develop the Hamiltonian analysis for this modified version, finding a best description of the results previously obtained. © 2010 Elsevier Inc.
Romero-Salazar C.,Institute For Materialphysik |
Jooss C.,Institute For Materialphysik |
Hernandez-Flores O.A.,Benito Juarez Autonomous University of Oaxaca
Physical Review B - Condensed Matter and Materials Physics | Year: 2010
The study of electric field distributions induced by flux creep in type-II superconducting films allows for important insight into the mechanism of vortex dynamics, the temporal evolution of flux and current distributions, and the occurrence of local losses. Most studies are based on the assumption that a phenomenological materials law, which has been extracted from macroscopic transport measurements, can be also applied to the local electric field during magnetization decay. We evaluate this ansatz by reconstructing the three-dimensional-induced Ei and potential Ep electric fields from experimentally measured time dependence of the flux density distribution. The results are quantitatively compared with solutions of the nonlinear and nonlocal equation of motion for the flux penetration, where the Maxwell equations as well as a materials law are utilized to obtain a two-dimensional Ei,2D and Ep,2D. We focus our analysis on the electric field distributions on a partially penetrated magnetized state of an epitaxial YBa2 Cu3 O6.95 film. © 2010 The American Physical Society.
Grajales-Coutino R.,Benito Juarez Autonomous University of Oaxaca |
Ibarra-Escamilla B.,National Institute of Astrophysics, Optics and Electronics |
Kuzin E.A.,National Institute of Astrophysics, Optics and Electronics
Applied Optics | Year: 2011
We propose and study experimentally and numerically a passively mode-locked figure-eight fiber laser scheme generating noiselike optical pulses, or subns wave packets with a fine inner structure of subps pulses presenting random amplitudes and durations. The particular design of the nonlinear optical loop mirror (NOLM) used in this laser, relying on nonlinear polarization rotation, allows adjusting the switching power through input polarization control. Experimental results show stable pulsed operation over a limited range of the NOLM input polarization angle. Interestingly, the spectral and temporal characteristics of these pulses are observed to be widely variable over that range. In particular, the spectral width varies from 16 to 52nm and this spectral variation is associated with an inverse evolution in the durations of the bunch and of the inner ultrashort pulses. Simulation results are in good agreement with the experiment. They confirm the strong dependence of the pulse properties on the value of the NOLM switching power, although NOLM switching is not alone responsible for the appearance of the noiselike pulsing mode. © 2011 Optical Society of America.
Cruz-Huerta J.,Autonomous University of the State of Morelos |
Salazar-Mendoza D.,Technological University of Mixteca |
Hernandez-Paredes J.,Autonomous University of the State of Morelos |
Hernandez Ahuactzi I.F.,Benito Juarez Autonomous University of Oaxaca |
Hopfl H.,Autonomous University of the State of Morelos
Chemical Communications | Year: 2012
The combination of two heteroaromatic boronic acids with pentaerythritol gave self-complementary tectons which were suitable for the generation of 2D and 3D molecular networks. © 2012 The Royal Society of Chemistry.