Unusual Rhythm Behind a Narrow Complex Tachycardia

info:eu-repo/semantics/publishedVersio

Nesting behaviour influences species-specific gas exchange across avian eggshells

Carefully controlled gas exchange across the eggshell is essential for the development of the avian embryo. Water vapour conductance (GH2O) across the shell, typically measured as mass loss during incubation, has been demonstrated to optimally ensure the healthy development of the embryo while avoiding desiccation. Accordingly, eggs exposed to sub-optimal gas exchange have reduced hatching success. We tested the association between eggshell GH2O and putative life-history correlates of adult birds, ecological nest parameters and physical characteristics of the egg itself to investigate how variation in GH2O has evolved to maintain optimal water loss across a diverse set of nest environments. We measured gas exchange through eggshell fragments in 151 British breeding bird species and fitted phylogenetically controlled, general linear models to test the relationship between GH2O and potential predictor parameters of each species. Of our 17 life-history traits, only two were retained in the final model: wet-incubating parent and nest type. Eggs of species where the parent habitually returned to the nest with wet plumage had significantly higher GH2O than those of parents that returned to the nest with dry plumage. Eggs of species nesting in ground burrows, cliffs and arboreal cups had significantly higher GH2O than those of species nesting on the ground in open nests or cups, in tree cavities and in shallow arboreal nests. Phylogenetic signal (measured as Pagel's λ) was intermediate in magnitude, suggesting that differences observed in the GH2O are dependent upon a combination of shared ancestry and species-specific life history and ecological traits. Although these data are correlational by nature, they are consistent with the hypothesis that parents constrained to return to the nest with wet plumage will increase the humidity of the nest environment, and the eggs of these species have evolved a higher GH2O to overcome this constraint and still achieve optimal water loss during incubation. We also suggest that eggs laid in cup nests and burrows may require a higher GH2O to overcome the increased humidity as a result from the confined nest microclimate lacking air movements through the nest. Taken together, these comparative data imply that species-specific levels of gas exchange across avian eggshells are variable and evolve in response to ecological and physical variation resulting from parental and nesting behaviours

La competencia de “Lolium perenne” RG afecta el rendimiento de uva y la calidad del vino de la región del Duero

To assess the efficacy of post-emergence herbicide programs in “Lolium perenne” L. populations glyphosate resistant (GR), a field experiment was carried out in a Douro vineyard (North Portugal) in 2014. A random block design (RBD) experiment with 11 treatments and three replicates was implemented. Fruit size, cluster number and grape weight were determined. Quality parameters (pH, total polyphenols anthocyanin content and color intensity) were also analysed. Analyses of variance (ANOVAs) were used to test the effects of weed cover on grape yield and quality. Tukey test was used to determine the differences among group means. The results show that weed cover affects crop productivity but it does not affect fruit composition, and therefore to wine quality.En 2014 se llevó a cabo un ensayo en un viñedo del Douro (Norte de Portugal) para evaluar la eficacia de diferentes herbicidas en post-emergencia sobre “L. perenne” GR. Se evaluó los efectos de la infestación en la productividad y calidad de la uva. La productividad se determinó midiendo el tamaño, peso y número de frutos y racimos. Los parámetros de calidad analizados fueron: pH, contenido de antocianinas, polifenoles totales e intensidad de color. El ensayo se dispuso en un diseño de bloques al azar con 11 tratamientos y 3 repeticiones. Se realizó el análisis de varianza (ANOVA) y la prueba de Tukey para observar las diferencias significativas entre la media de la eficacia, la productividad y la calidad. Los resultados obtenidos mostraron que la producción se vio afectada por la cobertura de “L. perenne”. Sin embargo, la composición del fruto, y por lo tanto la calidad del vino no se vio alterada

Boldness traits, not dominance, predict exploratory flight range and homing behaviour in homing pigeons

This study investigated whether consistent individual differences in behaviour (particularly exploratory tendency and object neophilia) were associated with the tendency to explore in free-ranging scenarios. This was tested in homing pigeons. The results showed that birds that were more likely to explore in the loft were also more likely to explore the local area during self-driven flights. When birds were released from a fixed release points, those which had explored less took more tortuous and longer routes back to the loft. This demonstrates the cost associated with lack of exploratory behaviour, and also links traits measured in laboratory scenarios to behaviour in free-ranging animals

Analysis of the ecological preferences of spontaneous vegetation. Case study applied to winter cereals

Se efectuaron 100 muestreos florísticos en parcelas de trigo, avena, cebada, caracterizándose algunas variables como el pH, textura del suelo, contenido en fósforo y potasio, precipitación, tipos de suelos y cultivos. Se realizó un análisis de frecuencias y abundancia de las especies. El método estadístico usado para las preferencias ecológicas fue el Método de los Perfiles Ecológicos e Información Mutua complementado con la aplicación del Método de Análisis Canónico de Correspondencias. Según el Método de Perfiles Ecológicos e Información Mutua, la distribución de la vegetación estudiada está estrechamente relacionada con la textura y pH. Los resultados de la aplicación del criterio de información Akaike y función ANOVA confirman los mismos factores como discriminantes en la distribución de la vegetación.It was Conducted 100 floristic surveys in fields of wheat, oat, barley together with the measurement of some variables, such as pH, soil texture, phosphorus and potassium content, precipitation, soil types and type of crops. An analysis of frequency and abundance of species was performed. The statistical method used for ecological preferences was the Ecological profiles and Mutual Information methodology complemented with the Canonical Correspondence Analysis methodology. According the Method of Ecological profiles and Mutual Information, the distribution of species is closely related to texture and pH. The application of Akaike information criterion and ANOVA function confirm the same factors as discriminating the distribution of vegetation

Study of autumn-winter weeds in Portugal and its ecological preferences

The conclusion of the dam project located in Alqueva, in Southern Portugal, has resulted in a significant increase of new irrigated areas, since 2006. This has meant that, in recent years, there have been progressive flora changes in farming systems traditionally implemented in the Alentejo region. The present work has analyzed the weed flora in an early stage of these changes, and the impact of environmental factors on the distribution of natural vegetation under Mediterranean climate conditions in the influence area of Alqueva. In 2007, 105 floristic surveys were carried out in autumn-winter crop plots or other soil use, and 264 species were identified. Families with higher expression were: Asteraceae, Poaceae, and Fabaceae. Only three species have been identified in more than half of farms, Avena sterilis, Phalaris minor and Lolium rigidum and they were part of the 15 species that revealed high and very high infestation degrees. Soil texture and extractable phosphorus have been determined as active ecological factors, according to the method of ecological profiles and Mutual Information. Therefore, these factores were those with the greatest influence on the species distribution. L. rigidum distribution showed to be associated with medium soil texture and A. sterilis distribution also showed to be associated with medium and fine soil texture soils, without showing ecological preference by extractable phosphorus. The distribution of P. minor was not related to the soil texture but showed preference for soils with medium phosphorus contentinfo:eu-repo/semantics/publishedVersio

Effects of age-related cognitive deficits on EEG phase coherence

Body and brain undergo several changes with aging. One of these changes is the loss of neuroplasticity, which leads to the decrease of cognitive abilities. Hence the necessity of stopping or reversing these changes is of utmost importance to contemporary society. In the present work, electroencephalogram (EEG) markers of cognitive decline are sought whilst the subjects perform the Wisconsin Card Sorting Test (WCST). Considering the expected age-related cognitive deficits, WCST was applied to young and elder participants. The results suggest that coherence on theta and alpha EEG rhythms decrease with aging and increase with performance. Additionally, theta phase coherence seems more sensitive to performance, while alpha synchronization appears as a potential ageing markerFCT-Foundation for Science and Technology and Compete Program with the project reference FCOMP-01-0124-FED ER-021145 (PTDC/SAU-ENB/118383/2010