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This research is focused on the evaluation of the reliability of regional landslide susceptibility models obtained by exploiting inhomogeneous (for quality, resolution and/or triggering related type and intensity) collected inventories for calibration. At a large-scale glance, merging more inventories can result in well-performing models hiding potential strong predictive deficiencies. An example of the limits that such kinds of models can display is given by a landslide susceptibility study, which was carried out for a large sector of the coastal area of El Salvador, where an apparently well-performing regional model (AUC = 0.87) was obtained by regressing a dataset through multivariate adaptive regression splines (MARS), including five landslide inventories from volcanic areas (Ilopango and Coatepeque caldera; San Salvador, San Miguel, and San Vicente Volcanoes). A multiscale validation strategy was applied to verify its actual predictive skill on a local base, bringing to light the loss in the predictive power of the regional model, with a lowering of AUC (20% on average) and strong effects in terms of sensitivity and specificity.

La goma de mezquite y huizache es una arabinogalactana proteica que comparte propiedades funcionales, con la goma arábiga. El objetivo de esta investigación fue evaluar la obtención de goma de mezquite (Prosopis laevigata Humb.) y huizache (Acacia farnesiana) con y sin aplicación de etileno, bajo condiciones de temporal, para potenciar su uso múltiple en sistemas agroforestales de zonas áridas y semiáridas de México. Se utilizó un diseño en bloques al azar con tres repeticiones y tres unidades de muestreo, con cinco tratamientos. En mezquite, al realizar incisión en tronco principal y aplicar la dosis de etileno, se obtuvieron 209.2 g, mientras que en rama secundaria, con el mismo procedimiento se logró un rendimiento de 207.6 g. En huizache, en tronco principal, se obtuvieron 1 076.7 g y en rama secundaria 1 049.5 g. No hubo variabilidad entre los bloques, pero sí entre los tratamientos. Como resultado del análisis químico proximal se encontró, en mezquite: humedad 10.25%, cenizas 2.63%, nitrógeno total 0.61%, extracto etéreo 2.29%, fibra 75%, carbohidratos 5.96% y taninos 0.27%. En huizache: humedad 12.65%, cenizas 3.69%, nitrógeno total 1.32%, extracto etéreo 2.95%, fibra 70.22%, carbohidratos 2.20% y taninos 0.15%. La goma de estas dos especies es un buen sustituto de la goma arábiga presentando un potencial similar e incluso mayor. En los tratamientos 2 y 3 se obtuvieron rendimientos superiores, en especial para Acacia farnesiana.

Background One of the main concerns of the modern medicine is the frightening spread of antimicrobial resistance caused mainly by the misuse of antibiotics. The researchers worldwide are actively involved in the search for new classes of antibiotics, and for the modification of known molecules in order to face this threatening problem. We have applied a computational approach to predict the interactions between a new cephalosporin derivative containing an additional β-lactam ring with different substituents, and several serine β-lactamases representative of the different classes of this family of enzymes. Results The results of the simulations, performed by using a covalent docking approach, has shown that this compound, although able to bind the selected β-lactamases, has a different predicted binding score for the two β-lactam rings, suggesting that one of them could be more resistant to the attack of these enzymes and stay available to perform its bactericidal activity. Conclusions The detailed analysis of the complexes obtained by these simulations suggests possible hints to modulate the affinity of this compound towards these enzymes, in order to develop new derivatives with improved features to escape to degradation. Electronic supplementary material The online version of this article (10.1186/s12900-018-0092-5) contains supplementary material, which is available to authorized users.

This is the first complete inventory of stingless bees in El Salvador. It includes the spatial distribution of wild and managed colonies and the relationships between their occurrence and vegetation cover, altitude and temperature. Applying a stratified sampling, we located wild colonies (n = 477) and managed colonies (n = 686) of stingless bees in tropical forests, agricultural fields and urban areas. Each stratum (14) was a department (political division) of El Salvador. We made maps of the distribution of the most common wild and managed species. We analysed spatial distribution of colonies through the Clark and Evans Index (CEI). For the estimation of diversity between departments, the Shannon-Wiener diversity index (H) was calculated. The relationship between species richness and vegetation cover was analysed through the chi-square test. Linear regression was used to evaluate the effects of altitude and temperature on species richness. We concluded that: (a) there are at least 20 species, six subgene...

Introduction . The nutritional and functional qualities of wild and cultivated Mexican serviceberry have not yet been reported. This species could have similar potential for commercialization to that of Saskatoon berry (Amelanchier alnifolia Nutt.). Materials and methods . Wild and cultivated fruits at two maturity stages were assessed for CIE Lab color, fruit size, titratable acidity and total soluble solids. Also, chemical composition and mineral contents were determined. In addition, vitamin C and simple phenols were assessed. Total soluble phenols, condensed tannins and anthocyanins as well as Trolox antioxidant activity and oxygen radical antioxidant activity were determined. Results . Fruit size, titratable acidity, total soluble solids, iron and simple phenols were higher in fruits of cultivated plants than in those of wild plants. Total fiber, calcium, vitamin C, total soluble phenols and condensed tannins were higher in wild fruits. Wild and cultivated serviceberry showed higher Trolox antioxidant activity compared with oxygen radical antioxidant activity. Caffeic, chlorogenic, coumaric and syringic acids and rutin were the predominant simple phenolics; they comprised from 59.3% (cultivated overripe fruit) to 76.9% (wild ripe fruit) of the sum of simple phenolics. The antioxidant activity of wild and cultivated fruit (258.3–699.2 mmol·kg–1 , fw) is up to 3.8 times higher compared with those of fruits commonly consumed. Conclusion . Contents of antioxidant compounds and the outstanding antioxidant activities of wild and cultivated Mexican serviceberry make this species a natural resource that could contribute to health.

Alternative berry crops belonging with the Rosaceae family currently have a great importance in the US and Canadian agribusiness, in this sense, the Mexican serviceberry (Malacomeles denticulata) is a fruit shrub mainly distributed in Mexico that has potential uses like horticultural crop; however, little information about its variability has been reported. That is why this research aims to determine the variability of M. denticulata by SSR markers. The apple SSR markers had a good transferability to Malacomeles (74 %); all transferable SSR are polymorphic and sixteen of them had high values of polymorphic information content, Nei’s expected heterozygosity (He), and Shannon’s information index (I), even the apple SSR loci were not previously proved in this species. Besides it was found high variability in the germplasm of central Mexico mainly within populations (72 %), where three different genetic pool were detected suggesting that a breeding program could be based in individual selection. That is why it is necessary select outstanding individual into population before to make hybridizations among these selected parents.

Este trabajo tuvo como objetivo evaluar los parametros CIELAB de luminosidad (L*), cromaticidad (C*) y el angulo de saturacion del color Hue (H°), asi como el contenido de taninos, fenoles totales y antocianinas en el fruto de dos poblaciones silvestres de membrillo cimarron en tres estados de madurez. La luminosidad (L*) se redujo 51 y 66 % para el fruto colectado en La Valenciana y El Derramadero, respectivamente. La cromaticidad (C*) del fruto disminuyo en niveles muy parecidos y los niveles de Hue se incrementaron. Los fenoles solubles totales disminuyeron de entre 763.0 y 834.5 mg-100 g1 en el estado inmaduro, de entre 497.5 y 538.5 mg-100 g1 en el estado sobremaduro. Los taninos condensados tambien se redujeron conforme el fruto maduro. Las antocianinas totales se incrementaron de entre 10.08 y 14.7 mg-100 g1 en el estado inmaduro, de entre 16.57 y 17.72 mg-100 g1 en el estado sobremaduro. El contenido de compuestos fenolicos y taninos en el membrillo cimarron es de 10 a 20 % mayor en comparacion con muchos frutos de consumo comun. Este fruto puede ser considerado un alimento con propiedades nutraceuticas

The genusMalacomeles(Decne.) G. N. Jones (RosaceaesubtribePyrinae) represents several fruit shrubs, which is mainly distributed in North and Central America, from southern USA to Honduras and Guatemala, although the main distribution of this genus is in Mexico. Five species of the genusMalacomeleshave been reported to exist in Mexico.Malacomelesis widely distributed in several mountainous ranges in Mexico, although it is unknown where most of the diversity of theMalacomelesgenus is located in the country. The aim of this biogeographic study was to determine the areas of highest diversity of the genusMalacomelesin Mexico based on species richness and diversity indices in order to identify the best regions of Mexico to collect germplasm. The results indicated that most of the diversity of the genusMalacomelesis concentrated in northeast Mexico, mainly in the biogeographic province of Sierra Madre Oriental. In this province, the highest values on three biodiversity indices were found. Thus, this area can be considered as the priority area to collect the germplasm ofMalacomeles.M. denticulatais the predominant and the most interesting species in Mexico from the viewpoint of collecting plant genetic resources; this species is mainly distributed in the provinces of Trans-Mexican Volcanic Axis, Mexican Plateau and Sierra Madre del Sur, where secondary priority areas to collect germplasm are located.

In recent years the market for berries has increased for fruits with antioxidant compounds that may play an important role in preventing diseases and improving health. The Mexican Amelanchier denticulata, which is commonly named "Membrillo cimarron", has potential for becoming a new berry crop. However, there are no ethnobotanical studies for this crop, and this study was initiated to collect information about the uses of A. denticulata in Central Mexico. This species grows in semiarid conditions and preliminary information indicates that it does not tolerate high water supply and may abort fruits under these conditions. Although preliminary observation gives some insight about the optimal conditions for this fruit crop, more detailed studies for improving agronomic practices are needed. The fruit consumption of Mexican serviceberry is limited to its natural distribution area in both the wild and in backyards. This fruit is very much appreciated by people in these areas, and it is used to make jellies, marmalades, and other typical candies for home use and for selling in local markets. A. denticulata is also used as a wood source. The wood is appreciated both for its good combustion characteristics, and also as a building material for construction. Moreover, the Mexican serviceberry is used as a fodder plant for feeding goats, and many people consider the milk from goats that have been fed with Mexican serviceberry to be of better quality.

Circumsporozoite (CS) protein is a malaria antigen involved in sporozoite invasion of hepatocytes, and thus considered to have good vaccine potential. We evaluated the polymorphism of the Plasmodium vivax CS gene in 24 parasite isolates collected from malaria-endemic areas of Colombia. We sequenced 27 alleles, most of which (25/27) corresponded to the VK247 genotype and the remainder to the VK210 type. All VK247 alleles presented a mutation (Gly → Asn) at position 28 in the N-terminal region, whereas the C-terminal presented three insertions: the ANKKAGDAG, which is common in all VK247 isolates; 12 alleles presented the insertion GAGGQAAGGNAANKKAGDAG; and 5 alleles presented the insertion GGNAGGNA. Both repeat regions were polymorphic in gene sequence and size. Sequences coding for B-, T-CD4(+), and T-CD8(+) cell epitopes were found to be conserved. This study confirms the high polymorphism of the repeat domain and the highly conserved nature of the flanking regions.

El género Crataegus (Rosaceae subtribu Pyrinae) es uno de los complejos taxonómicos más difíciles de tratar. Errores del pasado causan equivocaciones en la identificación de especies de este género, también existen nombres científicos que causan confusión en la determinación taxonómica. El presente trabajo tiene como objetivo describir la problemática, que existe en la taxonomía para este género y clarificar de la mejor manera la sistemática de los recursos genéticos del género Crataegus en México. Se plantea la posible identificación por zona geográfica el origen del tejocote (Crataegus spp.). El género Crataegus es complejo por sus distintos mecanismos reproductivos descritos como el problema Crataegus . En México, sólo existen dos tratados taxonómicos, uno a principios del siglo XX y el otro enfocado al norte y parte del centro de México, por lo que es conveniente efectuar estudios taxonómicos sobre este género para los estados de Puebla, Veracruz, Oaxaca, Guerrero, Morelos y Chiapas, donde las claves existentes son insuficientes para la identificación de los especímenes.

El objetivo de este trabajo fue determinar el posible desplazamiento de Crataegus mexicana DC. de las actuales zonas de adaptación, por efecto del cambio climático. Se hicieron dos modelos de zonas adecuadas de adaptación con los datos climáticos actuales y los del modelo CCM3, que predice el posible cambio climático al 2050. La mode- lación con los datos climáticos actuales muestra condiciones de adaptación que van de buenas a excelentes en las zonas de cultivo en el centro de México, así como condiciones similares para zonas del Eje Volcánico Transmexicano, Altiplano Mexicano, Sierra Madre Oriental y Sierra Madre del Sur. También presentó zonas con adaptación limitada en el noreste, noroeste y sur del país. En contraste, con el modelo CCM3 se mejoran las condiciones de muy buenas a excelentes, del Eje Volcánico Transmexicano incluyendo las actuales zonas de cultivo y en otras regiones del país. Por lo tanto, el tejocote se verá afectado de manera positiva por el cambio de la temperatura y la lluvia hacia el 2050, lo que podría ocasionar que se incremente su superficie cultivada.

El membrillo cimarrón (Amelanchier denticulata (Kunth) Koch.) es un arbusto frutal de la familia Rosaceae subtribu Pyrinae originario de México, del cual no existen estudios para conocer su diversidad ni su sistema reproductivo. Por estas razones y para tener un primer antecedente sobre su variabilidad morfológica, se caracterizaron seis poblaciones de A. denticulata originarias de Guanajuato, México, mediante caracteres de semilla. Todas las poblaciones presentaron alta variabilidad intra e interpoblacional. Las variables de semilla analizadas fueron discriminantes para distinguir las diferentes poblaciones, siendo las más importantes las relacionadas con las de tamaño de las semillas, seguidas de las de forma. El grado de apomixis no es claro en esta especie debido a la alta variación intrapoblacional; por lo tanto, se necesitan estudios más detallados para concluir la existencia o no de apomixis en A. denticulata.