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Pfeiler E.,Research Center En Alimentacion sarrollo | Johnson S.,University of California at San Diego | Marrow T.A.,University of California at San Diego
Journal of the Lepidopterists' Society | Year: 2012

Nucleotide sequence data from a segment of the mitochondrial cytochrome c oxidase subunit I (COI) gene, known as the barcode segment, were used to examine phylogenetic relationships and systematics of buckeye butterflies (Nymphalidae: Nymphalinae: Junonia) from the New World, with emphasis on taxa from western North America Three nominal species have been recognized for North America, J., evarete (Cramer) ,J. genoveva (Cramer), and J., coenia Hübner, with additional species recently proposed for the West Indies and northern South America The distinctive Andean buckeye , J ., vestina C. Felder & R. Felder, along with J. evarete and J., genoveva, are also components of the South American fauna With the exception ofJ., vestina, butterflies comprising the New World Junonia have had a confused taxonomie history, and species assignments are often problematic. Our results show that the barcode segment resolves the two major clades of New World Junonia, referred to here as clades A and B, with similar high support seen in an earlier phylogenetic study using both mitochondrial and nuclear genes. Within clade A ,J. vestina resolved in a basal position toJ., evarete from South America and the Caribbean. The data further suggest that species assignments in some populations of New World Junonia clustering in clade B (J. coenia + J. genoveva) need to be reevaluated. DNA barcodes, although failing to resolve all recognized species and subspecies level taxa of New World Junonia, probably owing to relatively recent divergences, can provide valuable tools for identifying the two major lineages, and when used in conjunction with morphological, ecological, behavioral and life history information can provide insights into the taxonomy and evolution of this difficult group. Source

Valenzuela-Martinez C.,University of Nebraska - Lincoln | Pena-Ramos A.,Research Center En Alimentacion sarrollo | Juneja V.K.,U.S. Department of Agriculture | Korasapati N.R.,University of Nebraska - Lincoln | And 2 more authors.
Journal of Food Protection | Year: 2010

Inhibition of Clostridium perfringens spore germination and outgrowth in ground turkey roast containing minimal ingredients (salt and sugar), by buffered vinegar (MOstatin V) and a blend (buffered) of lemon juice concentrate and vinegar (MOstatin LV) was evaluated. Ground turkey roast was formulated to contain sea salt (1.5%), turbinado sugar (0.5%), and various concentrations of MOstatin V (0.75, 1.25, or 2.5%) or MOstatin LV (1.5, 2.5, or 3.5%), along with a control (without MOstatins). The product was inoculated with a three-strain spore cocktail of C. perfringens to obtain initial spore levels of ca. 2.0 to 0.5 log CFU/g. Inoculated products were vacuum packaged, heat shocked for 20 min at 75°C, and cooled exponentially from 54.4 to 4.0°C in 6.5, 9, 12, 15, 18, or 21 h. In control samples without MOstatin V or MOstatin LV, C. perfringens populations reached 2.98, 4.50, 5.78, 7.05, 7.88, and 8.19 log CFU/g (corresponding increases of 0.51, 2.29, 3.51, 4.79, 5.55, and 5.93 log CFU/g) in 6.5, 9, 12, 15, 18, and 21 h of chilling, respectively. MOstatin V (2.5%) and MOstatin LV (3.5%) were effective in inhibiting C. perfringens spore germination and outgrowth in ground turkey roast to <1.0 log CFU/g during abusive chilling of the product within 21 h. Buffered vinegar and a blend (buffered) of lemon juice concentrate and vinegar were effective in controlling germination and outgrowth of C. perfringens spores in turkey roast containing minimal ingredients. Source

Mas J.F.,National Autonomous University of Mexico | Vega A.P.,University of Guanajuato | Reyes A.A.,Research Center En Alimentacion sarrollo | Santiago M.A.C.,Colegio de Mexico | Sandoval A.F.,National Autonomous University of Mexico
International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences - ISPRS Archives | Year: 2015

In order to identify drivers of land use / land cover change (LUCC), the rate of change is often compared with environmental and socio-economic variables such as slope, soil suitability or population density. Socio-economic information is obtained from census data which are collected for individual households but are commonly presented in aggregate on the basis of geographical units as municipalities. However, a common problem, known as the modifiable areal unit problem (MAUP), is that the results of statistical analysis are not independent of the scale and the spatial configuration of the units used to aggregate the information. In this article, we evaluate how strong MAUP effects are for a study on the deforestation drivers in Mexico at municipality level. This was done by taking socio-economic variables from the 2010 Census of Mexico along with environmental variables and the rate of deforestation. As population census is given for each human settlement and environmental variables are obtained from high resolution spatial database, it was possible to aggregate the information using spatial units ("pseudo municipalities") with different sizes in order to observe the effect of scale and aggregation on the values of bivariate correlations (Pearsons r) between pairs of variables. We found that MAUP produces variations in the results, and we observed some variable pairs and some configurations of the spatial units where the effect was substantial. Source

Chacon S.,Institute Ecologia | Tapia F.,Institute Ecologia | Esqueda M.,Research Center En Alimentacion sarrollo
Mycotaxon | Year: 2014

Ten dothideomycetous species were studied. New records for the Mexican mycobiota include Heptameria obesa, Leptospora rubella, Macrovalsaria megalospora, and Psiloglonium clavisporum, and an extended distribution for rarely reported dothideomycetes in Mexico is reported for Anteaglonium abbreviatum, Astrosphaeriella trochus, Gloniopsis praelonga, Hysterobrevium mori, Oedohysterium insidens, and Rhytidhysteron rufulum. Observations and photographs on macro- and microscopic characters are provided. © 2014. Mycotaxon, Ltd. Source

Flores D.I.,Research Center Cientifica Educacion Superior Of Ensenada | Sotelo-Mundo R.R.,Research Center En Alimentacion sarrollo | Brizuela C.A.,Research Center Cientifica Educacion Superior Of Ensenada
PLoS ONE | Year: 2014

The automatic identification of catalytic residues still remains an important challenge in structural bioinformatics. Sequence-based methods are good alternatives when the query shares a high percentage of identity with a well-annotated enzyme. However, when the homology is not apparent, which occurs with many structures from the structural genome initiative, structural information should be exploited. A local structural comparison is preferred to a global structural comparison when predicting functional residues. CMASA is a recently proposed method for predicting catalytic residues based on a local structure comparison. The method achieves high accuracy and a high value for the Matthews correlation coefficient. However, point substitutions or a lack of relevant data strongly affect the performance of the method. In the present study, we propose a simple extension to the CMASA method to overcome this difficulty. Extensive computational experiments are shown as proof of concept instances, as well as for a few real cases. The results show that the extension performs well when the catalytic site contains mutated residues or when some residues are missing. The proposed modification could correctly predict the catalytic residues of a mutant thymidylate synthase, 1EVF. It also successfully predicted the catalytic residues for 3HRC despite the lack of information for a relevant side chain atom in the PDB file. © 2014 Flores et al. Source

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