Improvements in the methylmercury extraction from human hair by headspace solid-phase microextraction followed by gas-chromatography cold-vapour atomic fluorescence spectrometry

Improvements in the methylmercury extraction from human hair by solid-phase microextraction followed by gas chromatography coupled to cold-vapour atomic fluorescence spectrometry (GC-CVAFS) have been carried out. They consisted in the optimisation of the digestion step prior to the aqueous-phase ethylation and in the GC-CVAFS interface set-up. The main digestion parameters such as acid type, concentration, temperature and time have been optimised for hair sample analysis, thereby avoiding methylmercury degradation. Moreover, the stability of the digested samples was evaluated to improve the sample throughput

The Fougueux (1785-1805): prototype of an 18th–19th century French construction method

The 74-gun French ship Fougueux (1785-1805) belonged to the Spanish-French fleet that faced the British in the Battle of Trafalgar on 21 October 1805. This warship was lost off the coast of Sancti Petri after the battle. About two centuries later, an array of iron cannons and wooden remains were studied at this site by the Underwater Archaeology Centre of Andalusia. This paper presents the results of the analysis of the ship’s construction method, whose particularities place it within the tradition of French naval construction between the late 18th century and early 19th century.Le navire français de 74 canons Le Fougueux (1785-1805) appartenait à la flotte franco-espagnole qui affronta les Britanniques lors de la bataille de Trafalgar le 21 octobre 1805. Ce navire de guerre fut perdu au large de Sancti Petri après la bataille. Environ deux siècles plus tard, un ensemble de canons de fer et de vestiges en bois ont été étudiés sur ce site par le Centre d’archéologie sousmarine d’Andalousie. Cet article présente les résultats de l’analyse des méthodes de construction du navire, que ses particularités placent dans la tradition de la construction navale française entre la fin du xviiie et le début du xixe siècle.Fil: Rodríguez Mariscal, Nuria E.. Centro de Arqueología Subacuática de Andalucía; EspañaFil: Ciarlo, Nicolás Carlos. Universidad de Buenos Aires. Facultad de Filosofía y Letras. Instituto de Arqueología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Alzaga García, Milagros. Centro de Arqueología Subacuática de Andalucía; EspañaFil: Rieth, Eric. Servicio de Patrimonio Histórico-artístico y Museo; EspañaFil: Izaguirre Lacoste, Manuel. Universite de Paris. Museum National D´historie Naturelle. Centre National de la Recherche Scientifique; Franci

Impact of oil on bacterial community structure in bioturbated sediments

Oil spills threaten coastlines where biological processes supply essential ecosystem services. Therefore, it is crucial to understand how oil influences the microbial communities in sediments that play key roles in ecosystem functioning. Ecosystems such as sediments are characterized by intensive bioturbation due to burrowing macrofauna that may modify the microbial metabolisms. It is thus essential to consider the bioturbation when determining the impact of oil on microbial communities. In this study, an experimental laboratory device maintaining pristine collected mudflat sediments in microcosms closer to true environmental conditions - with tidal cycles and natural seawater - was used to simulate an oil spill under bioturbation conditions. Different conditions were applied to the microcosms including an addition of: standardized oil (Blend Arabian Light crude oil, 25.6 mg.g21 wet sediment), the common burrowing organism Hediste (Nereis) diversicolor and both the oil and H. diversicolor. The addition of H. diversicolor and its associated bioturbation did not affect the removal of petroleum hydrocarbons. After 270 days, 60% of hydrocarbons had been removed in all microcosms irrespective of the H. diversicolor addition. However, 16S-rRNA gene and 16S-cDNA T-RFLP and RT-PCR-amplicon libraries analysis showed an effect of the condition on the bacterial community structure, composition, and dynamics, supported by PerMANOVA analysis. The 16S-cDNA libraries from microcosms where H. diversicolor was added (oiled and un-oiled) showed a marked dominance of sequences related to Gammaproteobacteria. However, in the oiled-library sequences associated to Deltaproteobacteria and Bacteroidetes were also highly represented. The 16S-cDNA libraries from oiled-microcosms (with and without H. diversicolor addition) revealed two distinct microbial communities characterized by different phylotypes associated to known hydrocarbonoclastic bacteria and dominated by Gammaproteobacteria and Deltaproteobacteria. In the oiled-microcosms, the addition of H. diversicolor reduced the phylotype-richness, sequences associated to Actinobacteria, Firmicutes and Plantomycetes were not detected. These observations highlight the influence of the bioturbation on the bacterial community structure without affecting the biodegradation capacities

A Broad Assessment of Factors Determining Culicoides imicola Abundance: Modelling the Present and Forecasting Its Future in Climate Change Scenarios

Bluetongue (BT) is still present in Europe and the introduction of new serotypes from endemic areas in the African continent is a possible threat. Culicoides imicola remains one of the most relevant BT vectors in Spain and research on the environmental determinants driving its life cycle is key to preventing and controlling BT. Our aim was to improve our understanding of the biotic and abiotic determinants of C. imicola by modelling its present abundance, studying the spatial pattern of predicted abundance in relation to BT outbreaks, and investigating how the predicted current distribution and abundance patterns might change under future (2011–2040) scenarios of climate change according to the Intergovernmental Panel on Climate Change. C. imicola abundance data from the bluetongue national surveillance programme were modelled with spatial, topoclimatic, host and soil factors. The influence of these factors was further assessed by variation partitioning procedures. The predicted abundance of C. imicola was also projected to a future period. Variation partitioning demonstrated that the pure effect of host and topoclimate factors explained a high percentage (>80%) of the variation. The pure effect of soil followed in importance in explaining the abundance of C. imicola. A close link was confirmed between C. imicola abundance and BT outbreaks. To the best of our knowledge, this study is the first to consider wild and domestic hosts in predictive modelling for an arthropod vector. The main findings regarding the near future show that there is no evidence to suggest that there will be an important increase in the distribution range of C. imicola; this contrasts with an expected increase in abundance in the areas where it is already present in mainland Spain. What may be expected regarding the future scenario for orbiviruses in mainland Spain, is that higher predicted C. imicola abundance may significantly change the rate of transmission of orbiviruses

Factors driving the abundance of Ixodes ricinus ticks and the prevalence of zoonotic I. ricinus-borne pathogens in natural foci

Environmental factors may drive tick ecology and therefore tick-borne pathogen (TBP) epidemiology, which determines the risk to animals and humans of becoming infected by TBPs. For this reason, the aim of this study was to analyze the influence of environmental factors on the abundance of immature-stage Ixodes ricinus ticks and on the prevalence of two zoonotic I. ricinus-borne pathogens in natural foci of endemicity. I. ricinus abundance was measured at nine sites in the northern Iberian Peninsula by dragging the vegetation with a cotton flannelette, and ungulate abundance was measured by means of dung counts. In addition to ungulate abundance, data on variables related to spatial location, climate, and soil were gathered from the study sites. I. ricinus adults, nymphs, and larvae were collected from the vegetation, and a representative subsample of I. ricinus nymphs from each study site was analyzed by PCR for the detection of Borrelia burgdorferi sensu lato and Anaplasma phagocytophilum DNA. Mean prevalences of these pathogens were 4.0% +/- 1.8% and 20.5% +/- 3.7%, respectively. Statistical analyses confirmed the influence of spatial factors, climate, and ungulate abundance on I. ricinus larva abundance, while nymph abundance was related only to climate. Interestingly, cattle abundance rather than deer abundance was the main driver of B. burgdorferi sensu lato and A. phagocytophilum prevalence in I. ricinus nymphs in the study sites, where both domestic and wild ungulates coexist. The increasing abundance of cattle seems to increase the risk of other hosts becoming infected by A. phagocytophilum, while reducing the risk of being infected by B. burgdorferi sensu lato. Controlling ticks in cattle in areas where they coexist with wild ungulates would be more effective for TBP control than reducing ungulate abundance.Peer reviewedVeterinary Pathobiolog

Stud book in the conservation and improvement of the horse

En cualquier programa de conservación racial y de selección y mejora genética equina, es imprescindible mantener un determinado grado de variabilidad genética, a lo largo de generaciones, mediante la preservación de los genotipos de los animales fundadores. El Libro Genealógico equino se convierte de esta forma en un instrumento esencial a la hora de determinar el grado de variabilidad genética de los individuos que integran una determinada población o raza ya que nos permite determinar parámetros tan importantes dentro de la genética como son: la consanguinidad, el coeficiente de parentesco, el número efectivo de fundadores en el pedigrí de un determinado animal y el porcentaje de influencia de los animales emblemáticos, fundadores y de estirpes o líneas dentro de la raza. El Libro Genealógico aporta al ganadero y al investigador la información genealógica más veraz por cuanto en la mayoría de estos Libros vienen regidos por organismos oficiales que realizan de forma seria y fiable un control de paternidad (mediante polimorfismo del suero, grupos sanguíneos, ADN, microchipado, etc...). En este trabajo se ha analizado el contenido de los Libros Genealógicos de las principales razas equinas explotadas en la Península Ibérica (P.R.E., P.S.L, P.R.á. y P.S.I.).In every breed preservation program of selection and genetic improvement, it is essential to maintain a certain degree of genetic variability over the generations by way of conservation of the genotypes of the founding animals. The Horse Genealogical Record Book is a necessity at the moment of determining the degree of genetic variabilities of the animals that form a determined breed and allows us to determine such important genetic parameters like: inbreeding, relationship coefficients, number of pedigree founders and blood lines with the breed. The Stud-Book gives the breeder and the investigator the most accurate genetic information because these records are normally compiled by official record keepers that carefully keep track of the paternity (by way of polymorphism of serum, blood types, DNA, microchipped, etc.). In the paper the contents of the Stud-Book of the main horse breeds in Iberian Peninsula (P.R.E., P.S.L, P.R.á. and P.S.I.) wed analysed

El libro genealógico en la conservación y mejora equina

En cualquier programa de conservación racial y de selección y mejora genética equina, es imprescindible mantener un determinado grado de variabilidad genética, a lo largo de generaciones, mediante la preservación de los genotipos de los animales fundadores. El Libro Genealógico equino se convierte de esta forma en un instrumento esencial a la hora de determinar el grado de variabilidad genética de los individuos que integran una determinada población o raza ya que nos permite determinar parámetros tan importantes dentro de la genética como son: la consanguinidad, el coeficiente de parentesco, el número efectivo de fundadores en el pedigrí de un determinado animal y el porcentaje de influencia de los animales emblemáticos, fundadores y de estirpes o líneas dentro de la raza. El Libro Genealógico aporta al ganadero y al investigador la información genealógica más veraz por cuanto en la mayoría de estos Libros vienen regidos por organismos oficiales que realizan de forma seria y fiable un control de paternidad (mediante polimorfismo del suero, grupos sanguíneos, ADN, microchipado, etc...). En este trabajo se ha analizado el contenido de los Libros Genealógicos de las principales razas equinas explotadas en la Península Ibérica (P. R. E., P. S. L., P. R.á y P. S. I.)