Palynology of acid-saline lakes of western Australiabiostratigraphy and paleoenvironmental reconstruction

Lakes are excellent repositories of fossils and sedimentary features that provide clues to past climatic and geologic events. Sediments from four cores drilled in Lake Aerodrome (LA1-09, LA2-09) and Lake Brown (LB1-09, LB2-09), two of the hundreds of ephemeral lakes in southern Western Australia, were analyzed for their palynological contents to understand the geologic and climatic evolution of the depositional basin. Palynofacies assemblages defined by statistical analyses of dispersed organic matter suggested differences in the depositional conditions and probable correlations between Lake Aerodrome cores. Detailed identifications and quantification of organic-walled microfossils yielded two palynomorph assemblages that reflect a climatic turnover: (1) a wet hinterland (rainforest), freshwater and swampy assemblage found in situ in the basal lignites of LA2-09 (44.58-59.63 meters); and (2) a sclerophyllic and halophilic assemblage in all younger sediments. The first and last appearances of key palynomorphs in the lignites, which contain Aglaoreidia cyclops (documented for the first time in Australia and the Southern Hemisphere), correlate the assemblage with the Middle Nothofagidites asperus Zone of the Werillup Formation. While Myrtaceidites lipsis constrains the age of the sediments from 23.38 meters depth to the top of LA2-09 as Pliocene to Recent, the sequence between 23.38 and 44.58 meters has long-ranging palynomorphs and is likely not older than the Miocene. Above the lignites, the salt-tolerant alga Dunaliella is used as a proxy for saline conditions. Reworking has been established in post-Eocene sediments because well-preserved Eocene freshwater and marine palynomorphs co-occur with sclerophyllic and halophilic palynomorphs --Abstract, page iii

Discrete but variable structure of animal societies leads to the false perception of a social continuum

Animal societies are typically divided into those in which reproduction within a group is monopolized by a single female versus those in which it is shared among multiple females. It remains controversial, however, whether these two forms of social structure represent distinct evolutionary outcomes or endpoints along a continuum of reproductive options. To address this issue and to determine whether vertebrates and insects exhibit the same patterns of variation in social structure, we examined the demographic and reproductive structures of 293 species of wasps, ants, birds and mammals. Using phylogenetically informed comparative analyses, we found strong evidence indicating that not all reproductive arrangements within social groups are viable in nature and that in societies with multiple reproductives, selection favours instead taxon-specific patterns of decrease in the proportion of breeders as a function of group size. These outcomes suggest that the selective routes to sociality differ depending upon whether monopolization of reproduction by one individual is possible and that variation within and among taxonomic groups may lead to the false perception of a continuum of social structures. Thus, the occurrence of very large societies may require either complete reproductive monopolization (monogyny/singular breeding) or the maintenance of a taxon-specific range of values for the proportional decrease in the number of breeders within a group (polygyny/plural breeding), both of which may reduce reproductive conflict among females

La formación de valores en la historia de la educación colombiana

El presente artículo esta orientado describir el pasado, el presente y las tendencias de la formación de valores en la educación superior colombiana. Inicialmente se hace un recuento histórico de las diferentes épocas de la educación colombiana, la cual estuvo influenciada desde sus comienzos por la religión católica tendencia que permaneció incólume desde la colonia hasta finales de 1970. Posteriormente y en especial en las postrimerías del siglo XX, se presentaron varios acontecimientos que incidieron para que el objetivo de formar valores fuera perdiendo importancia hasta quedar totalmente relegado, estos sucesos fueron : a) el vertiginoso avance científico y técnico que se presentó después de los años setenta incidiendo para que nuestros directivos encargados de orientar la políticas de la educación superior terminaran privilegiando, la instrucción sobre la educación y b) los fenómenos de narcotráfico, guerrilla y corrupción que han venido recorriendo nefastamente, el territorio nacional transformaron el tejido axiológico sobre el cual se cimentaba la sociedad colombiana. Por fortuna con el advenimiento del siglo XXI, la formación en: ética, moral y valores se ha convertido en una recomendación universal emanada desde la UNESCO. En los foros y congresos sobre educación e los ámbitos: internacional, nacional, regional y locales, el tema de formación en valores ha saltado a la palestra y se ha convertido en una tendencia de primera línea. En este sentido, la educación superior colombiana deberá hacer un gran esfuerzo en los próximos años para recuperar la formación integral de estudiante colombiano, deberá por tanto diseñar políticas, establecer programas y trazar tareas que permitan recuperar la urdimbre axiológica, visión explicitada en la parte final de este artículo para que en nuestras facultades y carreras se introduzcan mecanismos que permitan formar ciudadanos integrales esto es: instruidos y éticos

Big brains stabilize populations and facilitate colonization of variable habitats in birds

The cognitive buffer hypothesis posits that environmental variability can be a major driver of the evolution of cognition because an enhanced ability to produce flexible behavioural responses facilitates coping with the unexpected. Although comparative evidence supports different aspects of this hypothesis, a direct connection between cognition and the ability to survive a variable and unpredictable environment has yet to be demonstrated. Here, we use complementary demographic and evolutionary analyses to show that among birds, the mechanistic premise of this hypothesis is well supported but the implied direction of causality is not. Specifically, we show that although population dynamics are more stable and less affected by environmental variation in birds with larger relative brain sizes, the evolution of larger brains often pre-dated and facilitated the colonization of variable habitats rather than the other way around. Our findings highlight the importance of investigating the timeline of evolutionary events when interpreting patterns of phylogenetic correlation

Gobernación de risaralda y universidad tecnológica de pereira unidas para fortalecer la metrología regional

En este documento se muestran algunos resultados del trabajo conjunto entre la Gobernación de Risaralda y la Universidad Tecnológica de Pereira para fortalecer la Red Regional de Normalización, Certificación y Metrología en el Eje Cafetero

Gobernación de risaralda y universidad tecnológica de pereira unidas para fortalecer la metrología regional

En este documento se muestran algunos resultados del trabajo conjunto entre la Gobernación de Risaralda y la Universidad Tecnológica de Pereira para fortalecer la Red Regional de Normalización, Certificación y Metrología en el Eje Cafetero

High-throughput analysis of adaptation using barcoded strains of Saccharomyces cerevisiae

Background: Experimental evolution of microbes can be used to empirically address a wide range of questions about evolution and is increasingly employed to study complex phenomena ranging from genetic evolution to evolutionary rescue. Regardless of experimental aims, fitness assays are a central component of this type of research, and low-throughput often limits the scope and complexity of experimental evolution studies. We created an experimental evolution system in Results: We first confirm that barcode insertions do not alter fitness and that barcode sequencing can be used to efficiently detect fitness differences via pooled competition-based fitness assays. Next, we examine the effects of ploidy, chemical stress, and population bottleneck size on the evolutionary dynamics and fitness gains (adaptation) in a total of 76 experimentally evolving, asexual populations by conducting 1,216 fitness assays and analyzing 532 longitudinal-evolutionary samples collected from the evolving populations. In our analysis of these data we describe the strengths of this experimental evolution system and explore sources of error in our measurements of fitness and evolutionary dynamics. Conclusions: Our experimental treatments generated distinct fitness effects and evolutionary dynamics, respectively quantified via multiplexed fitness assays and barcode lineage tracking. These findings demonstrate the utility of this new resource for designing and improving high-throughput studies of experimental evolution. The approach described here provides a framework for future studies employing experimental designs that require high-throughput multiplexed fitness measurements

Aplicación de un método basado en el desempeño para el análisis y diseño sismo resistente de puentes de concreto reforzado

It proposes an application of a methodology that nalyzes the ability of a structural element, based on a geometric pre-dimensioning and a reinforcement supposed, finding from internal equilibrium curvatures to calculate displacements, ductility’s and seismic forces resistant, so that acceleration can be verified with the design spectrum of the seismic zone of the site, elastic or inelastic. This method allows simultaneous analysis and structural design and managing some important parameters for optimal seismic performance of bridges.Propone una aplicación de una metodología que analice la capacidad de un elemento estructural, basada en un pre-dimensionamiento geométrico y un supuesto refuerzo, encontrando a partir de las curvaturas de equilibrio interno para calcular desplazamientos, ductilidad y resistencia sísmica, para que la aceleración pueda ser verificada con El espectro de diseño de la zona sísmica del sitio, elástico o inelástico. Este método permite el análisis simultáneo y el diseño estructural y la gestión de algunos parámetros importantes para un rendimiento sísmico óptimo de los puentes

Dasyprocta punctata como especie emblemática de las zonas urbanas de Armenia, Quindío: Un caso de suplementación alimenticia

This work sought to describe the process of food supplementation to the guatines and in general to wildlife in the neighborhood of Mercedes del Norte, Comuna 10, Armenia, Quindío (4 ° 33'12 ”N and 75 ° 40'54” W; 1,480 masl; Figure 1). The neighborhood is made up of 32 blocks and 659 single-family and two-story single-family and two-story homes, housing an estimated population of 2416 inhabitants (Mayor's Office of Armenia, 2012), likewise, this neighborhood is surrounded by two strips of guadual (Guadua angustifolia ) with few trees and shrubs.Este trabajo buscó describir el proceso de suplementación de alimento hacia los guatines y en general a la fauna silvestre en el barrio Mercedes del Norte, Comuna 10, Armenia, Quindío (4°33’12” N y 75°40’54” O; 1.480 msnm; Figura 1). El barrio está constituido por 32 manzanas y 659 viviendas unifamiliares y bifamiliares de uno o dos pisos, albergando una población estimada de 2416 habitantes (Alcaldía de Armenia, 2012), así mismo, este barrio se encuentra rodeado por dos franjas de guadual (Guadua angustifolia) con pocos árboles y arbustos