Tensioactivos. XX. ω-Monoésteres grasos de ditioacetales de azúcares

The preparation of 5-O-lauroyl(myhstoyl, palmitoyl)-D-arabinose ethylendithioacetals, 6-O-lauroyl-D-glucose(D-galactose) ethylendithioacetals and 6-O-decanoyl(lauroyl)-D-mannose ethylendithioacetals is reported. The preparation of 5-O-octanoyl(decanoyl, lauroyl)-L-arabinose diethyldithioacetais is also reported. These compounds were obtained by monoesterification of aldosedithioacetals with the corresponding fatty acid chlorides in pyridine.Se describe la preparación de etilenditioacetales de la 5-O-lauroil(miristoil, palmitoil)- D-arabinosa, de la 6-O-lauroil-D-glucosa(D-galactosa) y de la 6-O-decanoil(lauroil)-D-manosa; y la preparación de dietilditioacetales de la 5-O-octanoil(decanoil, lauroil)-L-arabinosa. La síntesis de estos compuestos se ha realizado por monoesterificación de los ditioacetales de azúcares con los correspondientes cloruros de ácidos grasos en piridina

Seguimiento de la diversidad de líquenes y cambio climático en Sierra Nevada (España)

Lichens are common organisms in high mountain zones, where they play an important role in ecosystem balance. In recent years, the increasing interest in understanding more about their interactions with abiotic factors has prompted several investigations, some of which have proved their value as bioindicators of climatic conditions. In this context, focusing on climatic change effects on high mountain vascular plants and supported by the Global Observation Research Initiative in Alpine Environments project (GLORIA), we have monitored for the first time the lichens biodiversity in Sierra Nevada with the intention of studying the alterations caused by the process of climatic change. The aim of this paper is to explain the monitoring experience developed on the massif and contribute to the first results from the biodiversity and statistical analysis of the sampling data.Los líquenes son organismos comunes en las zonas de alta montaña donde juegan un importante papel en el equilibrio de los ecosistemas. En los últimos años, el creciente interés por entender más acerca de sus interacciones con los factores abióticos ha motivado diversas investigaciones, algunas de las cuales han demostrado su valor como bioindicadores de las condiciones climáticas. En este contexto, centrándonos en los efectos del cambio climático en plantas vasculares de alta montaña y respaldados por el proyecto “Iniciativa para la investigación y el seguimiento global de los ambientes alpinos (GLORIA)”, se ha monitorizado por primera vez la diversidad de líquenes en Sierra Nevada con la intención de estudiar las posibles alteraciones que esta pueda sufrir causadas por el proceso de cambio climático. El objetivo de este artículo es el de dar a conocer la experiencia de seguimiento en el macizo y aportar los primeros resultados procedentes del análisis, tanto de la biodiversidad como estadístico, de los datos de muestreo

Vegetation and geochemical responses to Holocene rapid climate change in the Sierra Nevada (southeastern Iberia): the Laguna Hondera record

High-altitude peat bogs and lacustrine records are very sensitive to climate changes and atmospheric dust input. Recent studies have shown a close relationship between regional climate aridity and enhanced eolian input to lake sediments. However, changes in regional-scale dust fluxes due to climate variability at short scales and how alpine environments were impacted by climatic- and human-induced environmental changes are not completely understood.Here we present a multi-proxy (palynological, geochemical and magnetic susceptibility) lake sediment record of climate variability in the Sierra Nevada (southeastern Iberian Peninsula) over the Holocene. Magnetic susceptibility and geochemical proxies obtained from the high mountain lake record of Laguna Hondera evidence humid conditions during the early Holocene, while a trend towards more arid conditions is recognized since  ∼ 7000&thinsp;cal&thinsp;yr&thinsp;BP, with enhanced Saharan eolian dust deposition until the present. This trend towards enhanced arid conditions was modulated by millennial-scale climate variability. Relative humid conditions occurred during the Iberian Roman Humid Period (2600–1450&thinsp;cal&thinsp;yr&thinsp;BP) and predominantly arid conditions occurred during the Dark Ages and the Medieval Climate Anomaly (1450–650&thinsp;cal&thinsp;yr&thinsp;BP). The Little Ice Age (650–150&thinsp;cal&thinsp;yr&thinsp;BP) is characterized in the Laguna Hondera record by an increase in runoff and a minimum in eolian input. In addition, we further suggest that human impact in the area is noticed through the record of Olea cultivation, Pinus reforestation and Pb pollution during the Industrial Period (150&thinsp;cal&thinsp;yr&thinsp;BP–present). Furthermore, we estimated that the correlation between Zr and Ca concentrations stands for Saharan dust input to the Sierra Nevada lake records. These assumptions support that present-day biochemical observations, pointing to eolian input as the main inorganic nutrient source for oligotrophic mountain lakes, are comparable to the past record of eolian supply to these high-altitude lakes.</p

Modelos de endemicidad a lo largo de un gradiente altitudinal en Sierra Nevada (España) y Lefka Ori (Creta, Grecia)

Aim: High mountains in the Mediterranean region of Europe are particularly rich in endemic vascular plants. We aimed to compare the altitudinal patterns of vascular plant species richness and the proportion of endemic species in two Mediterranean region: Lefka Ori on the island of Crete (Greece) and Sierra Nevada on the Iberian peninsula. Location: Sierra Nevada, Granada (Spain); Lefka Ori, Crete (Greece). Methods: Data from standardised permanent plots settings on summit sites (comprising eight plot sectors, covering the upeermost 10 altitudinal metres) of different elevations were used (GLORIA Multi-Summit approach; www.gloria.ac.at). Species numbers, rates of endemic species, and soils temperature were compared by means of ANCOVA and linear regression. Results: The two regions, though climatically similar, showed strikingly different patterns: In Sierra Nevada, the proportion of endemic vascular plants (species restricted to Sierra Nevada) showed a stepwise increase from the lowest to the highest summit. In contrast, the proportion of endemic species restricted to Crete was not significantly different between the four summits in Lefka Ori. In both regions the observed trends were largely consistent with the altitudinal distribution of the endemic species obtained from standard floras. Main conclusions: The geographic positions of the two regions, i.e. island versus mainland and the higher elevation of Sierra Nevada are suggested to be the primary causes of the observed differences. The high degree of endemism in the cold environments of Mediterranean mountains’ upper bioclimatic zones indicates a pronounced vulnerability to the impacts of climate change. A continued and intensified species monitoring in the mountains around the Mediterranean basin, therefore, should be considered as a priority research task.Objetivo: Las zonas de alta montaña en la región mediterránea europea son particularmente ricas en plantas vasculares endémicas. Nuestro objetivo es comparar los modelos altitudinales para la riqueza de plantas vasculares y la proporción de endemismos en dos regiones mediterráneas: Lefka Ori en la isla de Creta (Grecia) y Sierra Nevada en la Península Ibérica. Localización: Sierra Nevada, Granada (España); Lefka Ori, Creta (Grecia). Método: Los datos proceden de un muestreo estandarizado en varias cimas situadas a diferentes altitudes (GLORIA Multi-Summit approach; www.gloria.ac.at). El número de especies, tasas de endemicidad, y temperatura del suelo se compararon por medio de ANCOVA y regresión lineal. Resultados: Las dos regiones objeto de análisis, aunque similares climáticamente, muestran patrones llamativamente diferentes: en Sierra Nevada, la proporción de plantas vasculares endémicas (especies restringidas a Sierra Nevada) muestra un incremento gradual desde la cima más baja a la más alta. En contraste, la proporción de endemismos restringidos a Creta no fue significativamente diferente entre las cuatro cimas de Lefka Ori. Las tendencias observadas en ambas regiones fueron en gran parte consistentes con la distribución de las especies endémicas obtenida de las floras para cada región. Conclusiones principales: La posición geográfica de ambas regiones, por ejemplo. isla frente a continente, y la mayor elevación de Sierra Nevada se sugieren como las principales causas de las diferencias observadas. El alto grado de endemicidad en los ambientes fríos de las zonas bioclimáticas superiores de las montañas mediterráneas evidencia una marcada vulnerabilidad a los impactos del cambio climático. Por lo tanto, el seguimiento continuado e intensivo de las especies de montaña alrededor de la cuenca mediterránea, debería considerarse como una tarea investigadora prioritaria.He set up of the permanent plots and data collection was supported by the FP-5 project GLORIA-Europe (2001-2003) No EVK2-2000-00056 of the European Commission

Maresin 1 activates brown adipose tissue and promotes browning of white adipose tissue in mice

Objective Maresin 1 (MaR1) is a docosahexaenoic acid-derived proresolving lipid mediator with insulin-sensitizing and anti-steatosis properties. Here, we aim to unravel MaR1 actions on brown adipose tissue (BAT) activation and white adipose tissue (WAT) browning. Methods MaR1 actions were tested in cultured murine brown adipocytes and in human mesenchymal stem cells (hMSC)-derived adipocytes. In vivo effects of MaR1 were tested in diet-induced obese (DIO) mice and lean WT and Il6 knockout (Il6−/−) mice. Results In cultured differentiated murine brown adipocytes, MaR1 reduces the expression of inflammatory genes, while stimulates glucose uptake, fatty acid utilization and oxygen consumption rate, along with the upregulation of mitochondrial mass and genes involved in mitochondrial biogenesis and function and the thermogenic program. In Leucine Rich Repeat Containing G Protein-Coupled Receptor 6 (LGR6)-depleted brown adipocytes using siRNA, the stimulatory effect of MaR1 on thermogenic genes was abrogated. In DIO mice, MaR1 promotes BAT remodeling, characterized by higher expression of genes encoding for master regulators of mitochondrial biogenesis and function and iBAT thermogenic activation, together with increased M2 macrophage markers. In addition, MaR1-treated DIO mice exhibit a better response to cold-induced BAT activation. Moreover, MaR1 induces a beige adipocyte signature in inguinal WAT of DIO mice and in hMSC-derived adipocytes. MaR1 potentiates Il6 expression in brown adipocytes and BAT of cold exposed lean WT mice. Interestingly, the thermogenic properties of MaR1 were abrogated in Il6−/− mice. Conclusions These data reveal MaR1 as a novel agent that promotes BAT activation and WAT browning by regulating thermogenic program in adipocytes and M2 polarization of macrophages. Moreover, our data suggest that LGR6 receptor is mediating MaR1 actions on brown adipocytes, and that IL-6 is required for the thermogenic effects of MaR1

Mapa de series, geoseries y geopermaseries de vegetación de España (Memoria del mapa de vegetación potencial de España). Parte II

Peer Reviewe

Bridging the Gap Between National and Ecosystem Accounting Application in Andalusian Forests, Spain

National accounting either ignores or fails to give due values to the ecosystem services, products, incomes and environmental assets of a country. To overcome these shortcomings, we apply spatially-explicit extended accounts that incorporate a novel environmental income indicator, which we test in the forests of Andalusia (Spain). Extended accounts incorporate nine farmer activities (timber, cork, firewood, nuts, livestock grazing, conservation forestry, hunting, residential services and private amenity) and seven government activities (fire services, free access recreation, free access mushroom, carbon, landscape conservation, threatened biodiversity and water yield). To make sure the valuation remains consistent with standard accounts, we simulate exchange values for non-market final forest product consumption in order to measure individual ecosystem services and environmental income indicators. Manufactured capital and environmental assets are also integrated. When comparing extended to standard accounts, our results are 3.6 times higher for gross value added. These differences are explained primarily by the omission in the standard accounts of carbon activities and undervaluation of private amenity, free access recreation, landscape and threatened biodiversity ecosystem services. Extended accounts measure a value of Andalusian forest ecosystem services 5.4 times higher than that measured using the valuation criteria of standard accounts

Funcionalidad, implementación y líneas de desarrollo de la plataforma educativa SWAD / OpenSWAD

La plataforma de b-learning y gestión académica SWAD ofrece múltiples herramientas de apoyo a la gestión docente y al aprendizaje, y ha sido utilizada durante 19 años por 180.000 usuarios en la Universidad de Granada (UGR) y en los últimos 4 años por otros 23.000 usuarios procedentes de 1.500 instituciones educativas de todo el mundo. Este artículo resume las funcionalidades actuales de la plataforma y su implementación, y propone la incorporación de una serie de técnicas como son la gamificación, la geolocalización y la minería de datos con los objetivos de mejorar la motivación y el rendimiento académico de los estudiantes y de facilitar al profesorado las tareas de evaluación.The b-learning and academic management platform SWAD offers multiple tools to support teaching management and learning, and has been used for 19 years by 180,000 users at the University of Granada (UGR) and in the last 4 years by other 23,000 users from 1,500 educational institutions around the world. This article summarizes the current functionalities of the platform and its implementation, and proposes the incorporation of a series of techniques such as gamification, geolocation and data mining with the goals of improving students' motivation and academic performance, and supporting teachers in assessment tasks.Universidad de Granada: Departamento de Arquitectura y Tecnología de Computadore