Search results for "cola"
showing 10 items of 3122 documents
Non-Linearity Extremum in Niobium Doped Potassium Tantalate
1997
We report non-linear dielectric measurements in the KTaO 3 :Nb system (x Nb ≤ 0.05). The non-linear susceptibility diverges at low temperatures and reaches maximum values in the intermediate range (0.0075 ≤ x Nb ≤ 0.02). To account for this extremum non linearity, we propose a model of temperature dependent clusters which fits with a number of experimental reports. We also suggest that this model may be applied to the related compounds SrTiO 3 :Ca and KTaO 3 :Na.
Analysing the effect of land use and vegetation cover on soil infiltration in three contrasting environments in northeast Spain
2017
Este estudio presenta el análisis conjunto de la información obtenida a partir de 195 ensayos de infiltración en el campo, que fueron realizados mediante dispositivos de doble anillo. Los experimentos se realizaron en 20 situaciones contrastadas de usos del suelo, los cuales se encuentran distribuidos en tres contextos geográficos (costa NE de Cataluña, monte bajo del sector central del valle del Ebro y montaña media de la vertiente Sur del Pirineo central). El objetivo de esta investigación es determinar los factores más importantes que explican la variabilidad de la infiltración: uso del suelo, tipo de cubierta vegetal, características del suelo y del substrato rocoso, humedad del suelo y…
Prediction of Soil Formation as a Function of Age Using the Percolation Theory Approach
2018
Recent modeling and comparison with field results showed that soil formation by chemical weathering, either from bedrock or unconsolidated material, is limited largely by solute transport. Chemical weathering rates are proportional to solute velocities. Nonreactive solute transport described by non-Gaussian transport theory appears compatible with soil formation rates. This change in understanding opens new possibilities for predicting soil production and depth across orders of magnitude of time scales. Percolation theory for modeling the evolution of soil depth and production was applied to new and published data for alpine and Mediterranean soils. The first goal was to check whether the e…
Evaluación de los procesos superficiales de escorrentía en cárcavas originadas en olivares convencionales. Un apartado a tener en cuenta en la planif…
2019
RESUMEN Se analiza la respuesta hidrológica de una cárcava efímera frente a un evento de lluvia equivalente de frecuencia "ordinaria" (=1 año) a partir de una simulación de escorrentía en una cuenca experimental con olivar en Puente Genil, Córdoba (España). Mil litros de agua fueron bombeados durante 10 minutos y la descarga total, la velocidad superficial de avance de frente de flujo, la concentración de sedimentos y los cambios morfológicos en el perfil transversal fueron calculados. Los resultados mostraron elevadas diferencias entre las tasas de escorrentía de hasta un 17% entre las condiciones "secas" y "húmedas". La concentración de sedimentos instantánea llegó a alcanzar valores de h…
Summer air temperature, reconstructions from the last glacial stage based on rodents from the site Taillis-des-Coteaux (Vienne), Western France.
2014
AbstractThe oxygen isotope composition of phosphate from tooth enamel of rodents (δ18Op) constitutes a valuable proxy to reconstruct past air temperatures in continental environments. This method has been applied to rodent dental remains from three genera, Arvicola sp., Microtus sp. and Dicrostonyx sp., coming from Taillis-des-Coteaux, Vienne, France. This archaeological site contains an exceptionally preserved sedimentary sequence spanning almost the whole Upper Palaeolithic, including seven stratigraphic layers dated from 35 to 17 cal ka BP. The abundant presence of rodent remains offers the opportunity to quantify the climatic fluctuations coeval of the various stages of human occupation…
Palaeoecological implications of Neanderthal occupation at Unit Xb of El Salt (Alcoi, eastern Spain) during MIS 3 using small mammals proxy
2018
Nearly 250 small mammal remains from Unit Xb of El Salt Middle Palaeolithic site have been studied in order to reconstruct the palaeoecological conditions during a phase of Neanderthal occupation in this locality at 52.3 ± 4.6 ka. A total of 7rodents (Microtus arvalis, M. agrestis, M. (Terricola) duodecimcostatus, Microtus (Iberomys) cabrerae, Arvicola sapidus, Eliomys quercinus and Apodemus sylvaticus), 4 insectivores (Erinaceus cf. europaeus, Crocidura sp., Sorex sp. and Talpidae indet.) and 1 lagomorph (Oryctolagus cf. cuniculus) have been identified. Applying the Mutual Ecogeographic Range and Habitat Weighting methods, Unit Xb may correspond to a relatively cold (−3.3 °C in comparison …
Erratum to “Palaeoecological context for the extinction of the Neanderthals: A small mammal study of Stratigraphic Unit V of the El Salt site, Alcoi,…
2021
El Salt is an important reference site for understanding the extinction of Neanderthal populations in the eastern Iberian Peninsula during MIS 3. In this paper, we describe the small mammal assemblage from Stratigraphic Unit V, the youngest unit with evidence of human presence, based on nearly 1300 specimens. A total of seven rodents (Microtus arvalis, Microtus duodecimcostatus, Microtus cabrerae, Sciurus vulgaris, Arvicola sapidus, Eliomys quercinus and Apodemus sylvaticus), three insectivores (Talpa occidentalis, Crocidura sp., Sorex sp.) and one lagomorph (Oryctolagus cf. cuniculus) were identified. Palaeocological analyses point to drier conditions in this part of the stratigraphic sequ…
Palaeoecological context for the extinction of the Neanderthals: A small mammal study of Stratigraphic Unit V of the El Salt site, Alcoi, eastern Spa…
2019
El Salt is emerging as a reference site for the study of the extinction of Neanderthal populations in the Eastern Iberian Peninsula during MIS 3. The small vertebrate assemblage analysed in this work is framed within this general objective and comes from Stratigraphic Unit V, the most recent unit with human presence. Nearly 1300 small mammal remains have been studied in order to reconstruct the palaeoecological conditions of this debated period. A total of seven rodents (Microtus arvalis, Microtus duodecimcostatus, Microtus cabrerae, Sciurus vulgaris, Arvicola sapidus, Eliomys quercinus and Apodemus sylvaticus), three insectivores (Talpa occidentalis, Crocidura sp., Sorex sp.) and one lagom…
The targeted overexpression of SlCDF4 in the fruit enhances tomato size and yield involving gibberellin signalling
2020
AbstractTomato is one of the most widely cultivated vegetable crops and a model for studying fruit biology. Although several genes involved in the traits of fruit quality, development and size have been identified, little is known about the regulatory genes controlling its growth. In this study, we characterized the role of the tomato SlCDF4 gene in fruit development, a cycling DOF-type transcription factor highly expressed in fruits. The targeted overexpression of SlCDF4 gene in the fruit induced an increased yield based on a higher amount of both water and dry matter accumulated in the fruits. Accordingly, transcript levels of genes involved in water transport and cell division and expans…
Novel biocatalysts for glycerol conversion into 2,3-butanediol
2016
Abstract Bioconversion of biodiesel-derived waste glycerol into high-value products is proposed as a solution to improve economic viability of biorefineries. Several microorganisms are able to metabolize glycerol into 2,3-butanediol (2,3-BD), a promising bulk chemical with wide applications: solvent, fuel additive, and feedstock for synthetic rubber production, among them. In the present work, a wide screening of microorganisms present both into the waste water treatment system in a biodiesel industry and in culture collections was carried out in order to evaluate their potential as new 2,3-BD producer biocatalysts. Two microorganisms for 2,3-BD production from glycerol as sole carbon sourc…