A fully automated flow injection atomic absorption system for the determination of copper traces in waters with on-line pre-concentration in an ion-exchange column

The paper describes the development of an automatic on-line column pre-concentration technique using a time based-flow injection atomic absorption spectrometry system. A manifold incorporating a micro-column containing 25 mg of Dowex 50W-X8 was used with a time-based injector for the pre-concentration and determination of copper in natural and drinking waters. The system features depend on the alternate positions of a solenoid valve. The 3σ detection limits, enrichment factors, sampling frequency, relative standard deviations and linear calibration graphs were, respectively, in the range 0.6-1.5 μg/l, 25-60, 15-30 measurements/h, 1.0-3.1% and 1-65 μg/ml for pre-concentration times of 1 min. The procedure was successfully applied to a range of water samples and the accuracy was assessed through recovery experiments, the analysis of certified reference water samples and by independent analysis by atomic absorption spectrometry with electrothermal atomization

Actividad tormentosa, marítima, litoral y microcontinental en ámbitos insulares. Un análisis geográfico aplicado a Mallorca

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Maritime, coastal and micro continental thunderstorm activity in insular areas. A geographical analysis in Mallorca

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Reference crop evapotranspiration database in Spain (1961-2014)

Obtaining climate grids describing distinct variables is important for developing better climate studies. These grids are also useful products for other researchers and end users. The atmospheric evaporative demand (AED) may be measured in terms of the reference evapotranspiration (ETo), a key variable for understanding water and energy terrestrial balances and an important variable in climatology, hydrology and agronomy. Despite its importance, the calculation of ETo is not commonly undertaken, mainly because datasets consisting of a high number of climate variables are required and some of the required variables are not commonly available. To address this problem, a strategy based on the spatial interpolation of climate variables prior to the calculation of ETo using FAO-56 Penman-Monteith equation was followed to obtain an ETo database for continental Spain and the Balearic Islands, covering the 1961-2014 period at a spatial resolution of 1.1 km and at a weekly temporal resolution. In this database, values for the radiative and aerodynamic components as well as the estimated uncertainty related to ETo were also provided. This database is available for download in the Network Common Data Form (netCDF) at https://doi.org/10.20350/digitalCSIC/8615 (Tomas-Burguera et al., 2019). A map visualization tool (http://speto.csic.es, last access: 10 December 2019) is available to help users download the data corresponding to one specific point in comma-separated values (csv) format. A relevant number of research areas could take advantage of this database. For example, (i) studies of the Budyko curve, which relates rainfall data to the evapotranspiration and AED at the watershed scale, (ii) calculations of drought indices using AED data, such as the Standardized Precipitation-Evapotranspiration Index (SPEI) or Palmer Drought Severity Index (PDSI), (iii) agroclimatic studies related to irrigation requirements, (iv) validation of climate models'' water and energy balance, and (v) studies of the impacts of climate change in terms of the AED

Pavement and heritage in historical cities. Some reflections about a singular intervention in Cordoba (Spain)

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Application of the Standardized Precipitation Evapotranspiration Index (SPEI) for drought analysis and monitoring: characteristics, recommendations and comparison with other indices

The complexity of drought quantification and analysis: • Droughts are difficult to pinpoint in time and space given different economic sectors and natural systems affected. • We identify a drought by its effects or impacts on different types of systems (agriculture, water resources, ecology, forestry, economy, etc.), but there is not a physical variable we can measure to quantify droughts. • Long-term drought objective metrics (streamflows, soil moisture, lake levels, etc.) are commonly not available. Moreover, using only objective metrics other relevant variables to determine drought severity (e.g. the atmospheric water demand) are not taken into account. • We use the so-called “DROUGHT INDICES” for drought quantification and analysis. Standardized Precipitation Evapotranspiration Index (SPEI): The SPEI uses the difference between precipitation and ETo. This represents a simple climatic water balance which is calculated at different time scales to obtain the SPEI. With a value for ETo, the difference between the precipitation (P) and PET for the month i is calculated according to: Di = Pi-EToi, The calculated D values are aggregated at different time scalesPeer Reviewe

High-resolution spatio-temporal analyses of drought episodes in the western Mediterranean basin (Spanish mainland, Iberian Peninsula)

The purpose of this research was to identify major drought events on the Spanish mainland between 1961 and 2014 by means of two drought indices, and analyze the spatial propagation of drought conditions. The indices applied were the standardized precipitation index (SPI) and the standardized evaporation precipitation index (SPEI). The first was calculated as standardized anomalies of precipitation at various temporal intervals, while the second examined the climatic balance normalized at monthly scale, incorporating the relationship between precipitation and the atmospheric water demand. The daily meteorological data from Spanish Meteorological Archives (AEMet) were used in performing the analyses. Within the framework of the DESEMON project, original data were converted into a high spatial resolution grid (1.1 km2) following exhaustive quality control. Values of both indices were calculated on a weekly scale and different timescales (12, 24 and 36 months). The results show that during the first half of the study period, the SPI usually returned a higher identification of drought areas, while the reverse was true from the 1990s, suggesting that the effect from atmospheric evaporative demand could have increased. The temporal propagation from 12- to 24-month and 36-month timescales analyzed in the paper seems to be a far from straightforward phenomenon that does not follow a simple rule of time lag, because events at different temporal scales can overlap in time and space. Spatially, the propagation of drought events affecting more than 25% of the total land indicates the existence of various spatial gradients of drought propagation, mostly east–west or west–east, but also north–south have been found. No generalized episodes were found with a radial pattern, i.e., from inland to the coast

Ancient origin of the CAG expansion causing Huntington disease in a Spanish population

25 p. Figuras, tablas, bibliografíaHuntington disease (HD, MIM# 143100) is an autosomal dominant neurodegenerative disorder characterized clinically by progressive motor impairment, cognitive decline, and emotional deterioration. The disease is caused by the abnormal expansion of a CAG trinucleotide repeat in the first exon of the huntingtin gene in chromosome 4p16.3. HD is spread worldwide and it is generally accepted that few mutational events account for the origin of the pathogenic CAG expansion in most populations. We have investigated the genetic history of HD mutation in 83 family probands from the Land of Valencia, Eastern Spain. An analysis of the HD/CCG repeat in informative families suggested that at least two main chromosomes were associated in the Valencian population, one associated with allele 7 (77 mutant chromosomes) and one associated with allele 10 (2 mutant chromosomes). Haplotype A-7-A (H1) was observed in 47 out of 48 phase-known mutant chromosomes, obtained by segregation analysis, through the haplotype analysis of rs1313770-HD/CCGrs82334, as it also was in 120 out of 166 chromosomes constructed by means of the PHASE program. The genetic history and geographical distribution of the main haplotype H1 were both studied by constructing extended haplotypes with flanking STRs D4S106 and D4S3034. We found that we were able to determine the age of the CAG expansion associated with the haplotype H1 as being between 4,700 and 10,000 years ago. Furthermore, we observed a nonhomogenous distribution in the different regions associated with the different extended haplotypes of the ancestral haplotype H1, suggesting that local founder effects have occurred.This work was supported by the Fondo de investigación Sanitaria (FIS grant 01/1159), the Instituto de Salud Carlos III (grant G03/56) for the Spanish Network on Cerebellar Ataxias, and the Generalitat Valenciana (grant GRUPOS03/015).Peer reviewe

Recent changes and drivers of the atmospheric evaporative demand in the Canary Islands

We analysed recent evolution and meteorological drivers of the atmospheric evaporative demand (AED) in the Canary Islands for the period 1961-2013. We employed long and high-quality time series of meteorological variables to analyse current AED changes in this region and found that AED has increased during the investigated period. Overall, the annual ETo, which was estimated by means of the FAO-56 Penman-Monteith equation, increased significantly by 18.2 mm decade-1 on average, with a stronger trend in summer (6.7 mm decade-1). In this study we analysed the contribution of (i) the aerodynamic (related to the water vapour that a parcel of air can store) and (ii) radiative (related to the available energy to evaporate a quantity of water) components to the decadal variability and trends of ETo. More than 90 % of the observed ETo variability at the seasonal and annual scales can be associated with the variability in the aerodynamic component. The variable that recorded more significant changes in the Canary Islands was relative humidity, and among the different meteorological factors used to calculate ETo, relative humidity was the main driver of the observed ETo trends. The observed trend could have negative consequences in a number of water-depending sectors if it continues in the future

Seasonal temperature trends on the Spanish mainland: A secular study (1916–2015)

Trends in seasonal mean values of maximum and minimum temperature are analysed in the Spanish mainland from the new MOTEDAS_century database. This new data set has been developed combining the digitalized archives from the Spanish Meteorological Agency (AEMET) with information retrieved from Annual Books published by the former Meteorological Agency dating back to 1916, and covers the period 1916–2015. In all four seasons, mean seasonal temperature of maximum (Tmax) and minimum (Tmin) increased. The raising occurred in two main pulses separated by a first pause around the middle of the 20th century, but differed among seasons and also between maximum and minimum temperature. Analysis of the percentage of land affected by significant trends in maximum temperature reveals two increasing phases in spring and summer for Tmax, and in spring, summer, and autumn for Tmin. However, winter Tmax only rose during the recent decades, and autumn Tmax in the first decades. Negative significant trends were found in extended areas in spring Tmax, and in spring, autumn, and summer Tmin, confirming the first pause around the 1940's–1960's. Trends of seasonal mean values of Tmax and Tmin are not significant for at least the last 25–35 years of the study period, depending on the season. The areas under significant positive trend are usually more extended for Tmin than Tmax at any season and period. Areas with significant trend expand and contract in time according to two spatial gradients: south-east to north-west (east-west) for Tmax, and west to east for Tmin. We hypothesize a relationship between atmospheric prevalent advection and relief as triggering factors to understand spatial and temporal differences in seasonal temperatures at regional scale during the 20th century in the Iberian Peninsula