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Teotitlan de Flores Magon, Mexico

El Colegio de México, A.C. is a prestigious Mexican institute of higher education, specializing in teaching and research in social science and humanities. This Institution received the Prince of Asturias Award for Social science in 2001. The library of El Colegio de México is one of the largest academic libraries in Mexico, and it contains one of the most important Latin American collections in social science and humanities.The college was founded in 1940 by the Mexican Federal Government, the Bank of Mexico , the National Autonomous University of Mexico , and the Fondo de Cultura Económica. After the Spanish Civil War, the President of Mexico Lázaro Cardenas created The House of Spain in Mexico to host the Spanish intellectuals in exile in that country. Under the direction of renowned intellectual Alfonso Reyes, the House of Spain became a higher education center, and was renamed El Colegio de México in 1940. The College now operates under a 1961 charter that allows the institution to provide college-level teaching in the fields of humanistic knowledge and social and political science. In 1976, the university's campus was moved from the Colonia Roma to its current location.The college encompasses seven separate academic centers, teaching a total of three degrees, seven master's degrees and eight doctorates. The campus is located in a purpose-built and architecturally striking building on the southern fringes of Mexico City, and it was designed by the prestigious Mexican architect Teodoro González de León. Wikipedia.

Perez-Lachaud G.,Colegio de Mexico
Entomologia Experimentalis et Applicata | Year: 2010

Polygynous parasitoid males may be limited by the amount of sperm they can transmit to females, which in turn may become sperm limited. In this study, I tested the effect of male mating history on copula duration, female fecundity, and offspring sex ratio, and the likelihood that females will have multiple mates, in the gregarious parasitoid Cephalonomia hyalinipennis Ashmead (Hymenoptera: Bethylidae: Epyrinae), a likely candidate for sperm depletion due to its local mate competition system. Males were eager to mate with the seven females presented in rapid succession. Copula duration did not differ with male mating history, but latency before a first mating was significantly longer than before consecutive matings. Male mating history had no bearing on female fecundity (number of offspring), but significantly influenced offspring sex ratio. The last female to mate with a given male produced significantly more male offspring than the first one, and eventually became sperm depleted. In contrast, the offspring sex ratio of first-mated females was female biased, denoting a high degree of sex allocation control. Once-mated females, whether sperm-depleted or not, accepted a second mating after a period of oviposition. Sperm-depleted females resumed production of fertilized eggs after a second mating. Young, recently mated females also accepted a second mating, but extended in-copula courtship was observed. Carrying out multiple matings in this species thus seems to reduce the cost of being constrained to produce only haploid males after accepting copulation with a sperm-depleted male. I discuss the reproductive fitness costs that females experience when mating solely with their sibling males and the reproductive fitness gain of males that persist in mating, even when almost sperm-depleted. Behavioural observations support the hypothesis that females monitor their sperm stock. It is concluded that C. hyalinipennis is a species with a partial local mating system. © 2010 The Author. Journal compilation © 2010 The Netherlands Entomological Society.

Perez-Rodriguez P.,Colegio de Mexico
G3 (Bethesda, Md.) | Year: 2012

In genome-enabled prediction, parametric, semi-parametric, and non-parametric regression models have been used. This study assessed the predictive ability of linear and non-linear models using dense molecular markers. The linear models were linear on marker effects and included the Bayesian LASSO, Bayesian ridge regression, Bayes A, and Bayes B. The non-linear models (this refers to non-linearity on markers) were reproducing kernel Hilbert space (RKHS) regression, Bayesian regularized neural networks (BRNN), and radial basis function neural networks (RBFNN). These statistical models were compared using 306 elite wheat lines from CIMMYT genotyped with 1717 diversity array technology (DArT) markers and two traits, days to heading (DTH) and grain yield (GY), measured in each of 12 environments. It was found that the three non-linear models had better overall prediction accuracy than the linear regression specification. Results showed a consistent superiority of RKHS and RBFNN over the Bayesian LASSO, Bayesian ridge regression, Bayes A, and Bayes B models.

Perez P.,Colegio de Mexico | De Los Campos G.,University of Alabama at Birmingham
Genetics | Year: 2014

Many modern genomic data analyses require implementing regressions where the number of parameters (p, e.g., the number of marker effects) exceeds sample size (n). Implementing these large-p-with-small-n regressions poses several statistical and computational challenges, some of which can be confronted using Bayesian methods. This approach allows integrating various parametric and nonparametric shrinkage and variable selection procedures in a unified and consistent manner. The BGLR R-package implements a large collection of Bayesian regression models, including parametric variable selection and shrinkage methods and semiparametric procedures (Bayesian reproducing kernel Hilbert spaces regressions, RKHS). The software was originally developed for genomic applications; however, the methods implemented are useful for many nongenomic applications as well. The response can be continuous (censored or not) or categorical (either binary or ordinal). The algorithm is based on a Gibbs sampler with scalar updates and the implementation takes advantage of efficient compiled C and Fortran routines. In this article we describe the methods implemented in BGLR, present examples of the use of the package, and discuss practical issues emerging in real-data analysis. © 2014 by the Genetics Society of America All rights reserved.

Appendini K.,Colegio de Mexico
Journal of Agrarian Change | Year: 2014

The transition in Mexico from a maize market once characterized by heavy state intervention along the entire maize-tortilla chain to the 'free market' of today has been a long and complex process. Over two decades, the production of maize has seen a radical transition both in the geographical location of maize agriculture and the type of farmers growing maize. In this paper, I argue that the restructuring of the domestic maize supply is due to policy decisions to support private agents in the maize market; hence the state did not withdraw its involvement but, rather, has had a key role in the construction of the 'free' maize market, with the result that domestic supply for the market is concentrated in the hands of relatively few agents and in relatively few regions. I discuss the background to these policies and analyse the programmes implemented by the state agency ASERCA (Apoyos y Servicios a la Comercialización Agropecuaria) that support the commercialization of maize. © 2013 John Wiley & Sons Ltd.

Shifting cultivation around the Calakmul Biosphere Reserve of Mexico, part of the Mesoamerican Biological Corridor, appears to be intensifying temporally through reductions in crop-fallow cycles, with potential impacts on species diversity in the regenerating forest patches surrounding the reserve. This paper documents the temporal intensity of shifting maize cultivation in the region and links it to the species diversity found in secondary vegetation of different ages following different crop-fallow cycles. It finds that younger secondary growth, which is increasing under intensification, has less diversity in species composition. Simultaneously, the concentration of cultivation practices appears to foster more patches in older and more species-diverse vegetation. The implications for the preservation of the region's forest remain uncertain, however, given the spatial concentration of open lands along two key axes, one which dissects the reserve. © 2010 Springer-Verlag.

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