Solvability of the G_2 Integrable System

It is shown that the 3-body trigonometric G_2 integrable system is exactly-solvable. If the configuration space is parametrized by certain symmetric functions of the coordinates then, for arbitrary values of the coupling constants, the Hamiltonian can be expressed as a quadratic polynomial in the generators of some Lie algebra of differential operators in a finite-dimensional representation. Four infinite families of eigenstates, represented by polynomials, and the corresponding eigenvalues are described explicitly.Comment: 18 pages, LaTeX, some minor typos correcte

An annotated list of the centipedes (Chilopoda) in the National Collection of Arachnids, Instituto de Biología, Universidad Nacional Autónoma de México

The National Collection of Arachnids, Instituto de Biología, Universidad Nacional Autónoma de México (México City) houses 476 chilopod samples, of which 197 are determined to genus and/or species. These are documented here and represent several new state records. Topotypes of eight species of centipedes described by R. V. Chamberlin also documented.La Colección Nacional de Arácnidos, del Instituto de Biología de la Universidad Nacional Autónoma de México (Ciudad de México), resguarda 476 muestras de quilópodos, de los que 197 están determinadas a nivel de género y/o especie. Algunas de estas muestras corresponden a nuevos registros estatales. Se documentan los topotipos de ocho especies de ciempiés descritos por R. V. Chamberlin

Caryophyllales 2015 in Berlin and the Global Caryophyllales Initiative

Fil: Arias, Salvador. Universidad Nacional Autónoma de México; MéxicoFil: Berendsohn, Walter G.. Freie Universität Berlin; AlemaniaFil: Borsch, Thomas. Freie Universität Berlin; AlemaniaFil: Flores Olvera, Hilda. Universidad Nacional Autónoma de México; MéxicoFil: Ochoterena, Helga. Universidad Nacional Autónoma de México; MéxicoFil: von Mering, Sabine. Freie Universität Berlin; AlemaniaFil: Zuloaga, Fernando Omar. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Botánica Darwinion. Academia Nacional de Ciencias Exactas, Físicas y Naturales. Instituto de Botánica Darwinion; Argentin

Colorful Associahedra and Cyclohedra

Every n-edge colored n-regular graph G naturally gives rise to a simple abstract n-polytope, the colorful polytope of G, whose 1-skeleton is isomorphic to G. The paper describes colorful polytope versions of the associahedron and cyclohedron. Like their classical counterparts, the colorful associahedron and cyclohedron encode triangulations and flips, but now with the added feature that the diagonals of the triangulations are colored and adjacency of triangulations requires color preserving flips. The colorful associahedron and cyclohedron are derived as colorful polytopes from the edge colored graph whose vertices represent these triangulations and whose colors on edges represent the colors of flipped diagonals.Comment: 21 pp, to appear in Journal Combinatorial Theory

E-México - building on success, for success

The paper details the ITC context for México, which is characterised by a low, but rapidly growing use of ICTS, and then examines at the recent E-México policy initiative launched by President Vincent Fox, in the light of México's considerable experience in using ICT for distance education. Finally the paper suggests that, by benchmarking against Finland (a country with a high use of ICTs in both business and education), México would derive considerable social, economic and educational benefits from the use of ICT

Characterization of Rhizobium grahamii extrachromosomal replicons and their transfer among rhizobia

Background Rhizobium grahamii belongs to a new phylogenetic group of rhizobia together with Rhizobium mesoamericanum and other species. R. grahamii has a broad-host-range that includes Leucaena leucocephala and Phaseolus vulgaris, although it is a poor competitor for P. vulgaris nodulation in the presence of Rhizobium etli or Rhizobium phaseoli strains. This work analyzed the genome sequence and transfer properties of R. grahamii plasmids. Results Genome sequence was obtained from R. grahamii CCGE502 type strain isolated from Dalea leporina in Mexico. The CCGE502 genome comprises one chromosome and two extrachromosomal replicons (ERs), pRgrCCGE502a and pRgrCCGE502b. Additionally, a plasmid integrated in the CCGE502 chromosome was found. The genomic comparison of ERs from this group showed that gene content is more variable than average nucleotide identity (ANI). Well conserved nod and nif genes were found in R. grahamii and R. mesoamericanum with some differences. R. phaseoli Ch24-10 genes expressed in bacterial cells in roots were found to be conserved in pRgrCCGE502b. Regarding conjugative transfer we were unable to transfer the R. grahamii CCGE502 symbiotic plasmid and its megaplasmid to other rhizobial hosts but we could transfer the symbiotic plasmid to Agrobacterium tumefaciens with transfer dependent on homoserine lactones. Conclusion Variable degrees of nucleotide identity and gene content conservation were found among the different R. grahamii CCGE502 replicons in comparison to R. mesoamericanum genomes. The extrachromosomal replicons from R. grahamii were more similar to those found in phylogenetically related Rhizobium species. However, limited similarities of R. grahamii CCGE502 symbiotic plasmid and megaplasmid were observed in other more distant Rhizobium species. The set of conserved genes in R. grahamii comprises some of those that are highly expressed in R. phaseoli on plant roots, suggesting that they play an important role in root colonization.Fil: Althabegoiti, Maria Julia. Universidad Nacional Autónoma de México; México. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Ormeño Orrillo, Ernesto. Universidad Nacional Autónoma de México; MéxicoFil: Lozano, Luis. Universidad Nacional Autónoma de México; MéxicoFil: Torres Tejerizo, Gonzalo Arturo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional Autónoma de México; MéxicoFil: Rogel, Marco Antonio. Universidad Nacional Autónoma de México; MéxicoFil: Mora, Jaime. Universidad Nacional Autónoma de México; MéxicoFil: Martinez Romero, Esperanza. Universidad Nacional Autónoma de México; Méxic

Consumer Price Behavior in Mexico Under Inflation Targeting: A Microdata Approach *

La serie de Documentos de Investigación del Banco de México divulga resultados preliminares de trabajos de investigación económica realizados en el Banco de México con la finalidad de propiciar el intercambio y debate de ideas. El contenido de los Documentos de Investigación, así como las conclusiones que de ellos se derivan, son responsabilidad exclusiva de los autores y no reflejan necesariamente las del Banco de México. The Working Papers series of Banco de México disseminates preliminary results of economic research conducted at Banco de México in order to promote the exchange and debate of ideas. The views and conclusions presented in the Working Papers are exclusively the responsibility of the authors and do not necessarily reflect those of Banco de México. Documento de Investigació

El Centro Urbano Presidente Alemán: un caso de apropiación de vivienda colectiva de mediados del s.XX en la Ciudad de México

El trabajo que aquí se presenta pretende estudiar un caso de vivienda colectiva analizando la arquitectura a partir de las prefiguraciones y refiguraciones a fin de observar las concordancias y definir los significados que el habitante proporciona a los espacios arquitectónicos, colectivos y privados. El caso que se pone a revisión es el Centro Urbano Presidente Alemán, proyecto arquitectónico de 1,080 apartamentos desarrollado por el Arq. Mario Pani y construido entre los años 1947 a 1949 en la Ciudad de México