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This paper aims to assess the impact of individual measures for NOx emission reduction on NO2 concentrations at very high spatial resolution in an urban district of Madrid City (Spain). A methodology based on a set of Computational Fluid Dynamics simulations for 16 meteorological scenarios combined with the CHIMERE model for background pollution is used to obtain annual NO2 concentration maps. Two scenarios included in the Spanish National Air Pollution Control Programme are investigated: NOx emission reductions from the installation of more efficient boilers for domestic heating (ECOBOIL) and from the partly substitution of passenger cars with combustion engines by electric cars (EC). This analysis is extended to 9 additional scenarios of more ambitious implementation of electric vehicles in order to determine what the NOx emission reduction required for the annual mean NO2 concentration EU limit value not being exceeded is. The ECOBOIL scenario has a very weak impact on the NO2 concentrations. However, the EC scenario implies a more significant reduction of the NO2 concentrations, but not enough to fully remove NO2 limit value exceedances in the study area. A small additional (compared with the EC scenario) implementation of electric vehicles seems to fulfil that the spatially averaged NO2 concentration be lower than the EU limit value, but the area with exceedances is still very large. However, stronger traffic emission reductions (80%) corresponding to the most ambitious scenarios are needed in order to reach that at least 95% of the domain is free of EU limit value exceedances. [ABSTRACT FROM AUTHOR]

The removal of water from mines was one of the key issues that former miners had to deal with. Roman colonists brought new technology to the Iberian Peninsula that addressed this problem. However, they did not invent this technology because it had already been applied to the growth of other endeavours in the Hellenistic society throughout the Eastern Mediterranean. In the mine, the Archimedes screw, waterwheels, bucket pulleys, and Ctesibius pumps were the primary drainage systems. In this essay, the primary characteristics, and modes of operation of machines are examined. Without leaving out the most significant finds made in the southwest of the Iberian Peninsula, one of the regions with the longest history of mining exploitation. To serve as a foundation for future research in this field, this work compares the primary mining mechanisms in ancient Huelva on a qualitative and quantitative level by the implementation of a TOPSIS methodology, a multi-criteria decision analysis method. [ABSTRACT FROM AUTHOR]

Soil functioning is closely linked to the interactions between biological communities with the physical environment. Yet, the impact of plant community attributes on metabolic processes promoting soil nutrient cycling remains largely unknown. We hypothesized that the plant community acts as a regulating agent of nutrient mobilization in soils according to the phylogenetic and morpho-functional traits of plant species of which it is composed. Rhizosphere soils were collected in autumn and spring under 32 tree and shrub species in two Mediterranean mixed forests (four plots in each) located in southern Spain, and nine soil enzymatic activities related to C, N and P mobilization were assessed. Phylogeny and morpho-functional traits of plant species were recorded and their imprint in soil enzymatic activities across forests was determined. The results showed a plant phylogenetic signal for N mobilization in both forests, while it varied across forests for non-labile C and P mobilization. The plant phylogenetic signals were primarily driven by lineages that diversified through the Miocene, about 25 Myr ago. In addition, leaf traits and plant's mycorrhizal type explained soil enzymatic activities independently from phylogeny. C and P mobilization increased under ectomycorrhizal plants, whilst enhanced N mobilization did occur under arbuscular mycorrhizal ones. The plant community composition led to a different carbon and nutrient mobilization degree, which in turn was mediated by distinct microbial communities mirroring differentiated resource-acquisition strategies of plants. Our results highlight the role of plant traits and mycorrhizal interactions in modulating carbon and nutrient cycling in Mediterranean mixed forest soils. [ABSTRACT FROM AUTHOR]

Aims : Many studies have reported beneficial effects of yeasts on the colonization and development of arbuscular mycorrhizae, thought a few studies have also shown neutral effects. All these studies have in common that the mechanism, by which yeasts and mycorrhizae interact, is little understood. Here, we explore how plant growth-promoting yeasts affect the colonization of tomato plants by beneficial mycorrhizal fungi. Methods: We tested the influence of the soil yeasts Candida saitoana, Tausonia pullulans, and Saccharomyces eubayanus on colonization of tomato roots by the mycorrhizal fungus Rhizophagus irregularis. We analyzed mycorrhizal parameters and the expression pattern of mycorrhiza-specific genes. In plants co-inoculated with S. eubayanus and R. irregularis, we measured the root accumulation pattern of jasmonic acid, oxo-phytodienoic acid, abscisic acid and salicylic acid, and the expression of genes related to plant hormone signaling and metabolism. Results: The three yeasts had distinct effects on mycorrhizal colonization: C. saitoana had no effect on mycorrhizal parameters, T. pullulans delayed mycorrhizal colonization at an early stage, and S. eubayanus slowed colonization down throughout the entire trial. In plants co-inoculated with S. eubayanus and R. irregularis, we observed a sustained increase in jasmonic acid and up-regulation of the JA biosynthesis related genes LOXD, OPR3, and AOS1. Conclusion: Co-inoculation with yeast affected mycorrhizal colonization and altered the expression pattern of mycorrhizal and plant defense-related genes. In particular, the yeast S. eubayanus modified plant defense hormones such as jasmonic acid, which is linked to mycorrhizal-induced resistance in tomato plants. [ABSTRACT FROM AUTHOR]

Background: The gut microbiota can impact older adults' health, especially in patients with frailty syndrome. Understanding the association between the gut microbiota and frailty syndrome will help to explain the etiology of age-related diseases. Low-grade systemic inflammation is a factor leading to geriatric disorders, which is known as "inflammaging". Intestinal dysbiosis has a direct relationship with low-grade systemic inflammation because when the natural gut barrier is altered by age or other factors, some microorganisms or their metabolites can cross this barrier and reach the systemic circulation. Objectives: This review had two general goals: first, to describe the characteristics of the gut microbiota associated with age-related diseases, specifically frailty syndrome. The second aim was to identify potential interventions to improve the composition and function of intestinal microbiota, consequently lessening the burden of patients with frailty syndrome. Methods: A search of scientific evidence was performed in PubMed, Science Direct, and Redalyc using keywords such as "frailty", "elderly", "nutrient interventions", "probiotics", and "prebiotics". We included studies reporting the effects of nutrient supplementation on frailty syndrome and older adults. These studies were analyzed to identify novel therapeutic alternatives to improve gut microbiota characteristics as well as subclinical signs related to this condition. Results: The gut microbiota participates in many metabolic processes that have an impact on the brain, muscles, and other organs. These processes integrate feedback mechanisms, comprising their respective axis with the intestine and the gut microbiota. Alterations in these associations can lead to frailty. We report a few interventions that demonstrate that prebiotics and probiotics could modulate the gut microbiota in humans. Furthermore, other nutritional interventions could be used in patients with frailty syndrome. Conclusion: Probiotics and prebiotics may potentially prevent frailty syndrome or improve the quality of life of patients with this disorder. However, there is not enough information about their appropriate doses and periods of administration. Therefore, further investigations are required to determine these factors and improve their efficacy as therapeutic approaches for frailty syndrome. [ABSTRACT FROM AUTHOR]

A hybrid system integrated by anaerobic filter–baffled subsurface horizontal constructed wetland (AFwet) was studied for treating polluted channel water, varying the hydraulic retention time (HRT) from 8 to 2 days. A conventional wetland (CW) and baffled conventional wetland (bCW) were used as control systems. The higher COD and ammonium nitrogen removal efficiencies were achieved at HRT of 8 days, of which the AFwet system was the best. At HRT of 2 days, COD removals for CW, bCW, and AFwet system were 54.22%, 72.96%, and 80.68%, respectively, whereas the ammonium removals were 34.16%, 50.07%, and 95.97%, correspondingly. The experimental results showed that the anaerobic filter intensified the ammonium removal, achieving removal efficiencies above 90%. The smallest footprint of 2.2 m2/PE (population equivalent) was obtained at hydraulic loading rate (HLR) of 0.14 m2/m3 day and organic loading rate (OLR) of 36.2 g COD/m2 day. Nowadays, footprint and pollutant removal are significant indicators for the choice of constructed wetland. [ABSTRACT FROM AUTHOR]

Industrial wastewater discharges pose an environmental risk. Here, the effectiveness of an up-flow vertical hybrid system, operating with synthetic and industrial wastewater was investigated, as a new approach to perform nitrification/denitrification and desulfurization within a single reactor. The hybrid reactor is divided in two reaction zones, the oxic and anoxic. The removal of chemical oxygen demand (COD), ammonium, and sulfide was investigated, highlighting changes in microbial diversity. The reactor was evaluated at hydraulic residence time (HRT) of 1.6 days, and its performance throughout 180 days is presented in four stages. In stages I–II, high COD and ammonium removal was obtained with synthetic wastewater. In stage-III, sulfide-rich synthetic wastewater did not alter the system, attaining COD, ammonium, and sulfide removal efficiencies of 81, 99.5, and 99.7%, respectively. In the last stage, a mixture of effluents was fed into the reactor at loading rates of 277 mg COD/L-d, 46.5 mg NH4+-N /L-d, and 15 mg HS−-S /L-d. Sulfide and ammonium removals were 100% and 99.9%, respectively. However, low COD removal was observed, being of 51%, and the system removed 97% in terms of BOD5. The structure and microbial diversity also changed. Sulfide feeding, induced the proliferation of sulfur oxidizers like Thiomiscropira and Thiobacillus. Industrial wastewater enhanced the abundance of Pseudomonas (15.53%) and favored the proliferation of new bacteria of the genus Truepera (2.98%) and Alicyclipilus (7.56%). This is the first study reporting simultaneous nitrification/denitrification and desulfurization to remove ammonium, COD and sulfide from complex industrial wastewater using an up-flow vertical hybrid reactor. [ABSTRACT FROM AUTHOR]

Graphene active sensors have demonstrated promising capabilities for the detection of electrophysiological signals in the brain. Their functional properties, together with their flexibility as well as their expected stability and biocompatibility have raised them as a promising building block for large-scale sensing neural interfaces. However, in order to provide reliable tools for neuroscience and biomedical engineering applications, the maturity of this technology must be thoroughly studied. Here, we evaluate the performance of 64-channel graphene sensor arrays in terms of homogeneity, sensitivity and stability using a wireless, quasi-commercial headstage and demonstrate the biocompatibility of epicortical graphene chronic implants. Furthermore, to illustrate the potential of the technology to detect cortical signals from infra-slow to high-gamma frequency bands, we perform proof-of-concept long-term wireless recording in a freely behaving rodent. Our work demonstrates the maturity of the graphene-based technology, which represents a promising candidate for chronic, wide frequency band neural sensing interfaces. Graphene active sensors have emerged as a promising building block for large-scale neural interfaces. The authors evaluate their performance in terms of wide frequency band sensitivity, stability and biocompatibility and perform proof-of-concept long-term wireless recording in a freely behaving rodent. [ABSTRACT FROM AUTHOR]

The realism of a specific configuration of the WRF Regional Climate Model (RCM) to represent the observed temperature evolution over the Iberian Peninsula (IP) in the 1971–2005 period has been analyzed. The E-OBS observational dataset was used for this purpose. Also, the added value of the WRF simulations with respect to the IPSL Earth System Model (ESM) used to drive the WRF RCM was evaluated. In general, WRF presents lower temperatures than in the observations (negative biases) over the IP. These biases are comparatively larger than those of the driving ESM. Once the biases are corrected, WRF provides an added value in terms of a higher spatial representation. WRF introduces more variability in some regions in comparison to gridded observation. Warming trends according to the observations are also well represented by the RCM. In the second part of this study, the projections of future climate performed with both the ESM and the RCM were evaluated for the RCP4.5 and RCP8.5 scenarios during the 21st century. Although both models simulate temperature increases, the RCM simulates a smaller warming than the ESM after the mid-21st century, except for winter. Using the WRF model, the maximum temperature increase reaches 6 ∘ C and 3 ∘ C for RCP8.5 and RCP4.5 in the south east of the Iberian Peninsula by the end of the 21st century, respectively. [ABSTRACT FROM AUTHOR]

This paper analyses the seismic vulnerability of various rammed earth medieval fortifications situated in Southeastern Spain, where seismic events with intensity over VII have taken place in the last millennium, using the vulnerability index method. This method begins with the choice of a certain initial value, V0, of the vulnerability index, which is obtained from a preset range between maximum, V 0 max , and minimum, V 0 min , values, which are likely for vulnerability indices, according to the constructive material characteristics and based on expert judgments. Rammed earth structures have not yet been studied using the vulnerability index method, despite the fact that they are quite common medieval structures in Spain and other countries in the Mediterranean region, many of which are also heritage sites, and hence are legally protected. Intervention priorities on them have been determined from the results in this paper with the aim of reducing their seismic vulnerability. For the different rammed earth techniques, a proposed primary value Vp = 0.76 together with some other material modifiers (construction typology and quality, current material porosity and density, and superficial deterioration) make the range of values V0 vary between 0.58 and 1.02. Moreover, structural behavior modifiers (MK) have been adapted to the various defensive rammed earth structural typologies used for these fortifications allowing us to obtain individualized vulnerability index values. Three rammed earth fortifications damaged by historical earthquakes and located in SE Spain have been used to validate the method, in which values of V0med range between 35.2 and 89.1% and upwards and the vulnerability index IVmed may vary between 27.9 and 70.7% and upwards as compared to those used by other authors for castles. Besides, the proposed method has been used by carefully choosing six rammed earth fortifications (two towers, two walls and two castles) in SE Spain which are representative of different construction systems, structural typologies and topographies. Furthermore, the mean damage grade and the probability of its occurrence is determined for each fortification based on PGA data and site effects, taking into account a probabilistic seismic scenario for a 975 year return period, in accordance with existing legislation. In the end, direct relations are established between the seismic vulnerability and the types of material and the typology of the fortifications. We have carried out a sensibility analysis in order to learn about the influence of the constructive technique, the material condition and the structural typology on the damage grade value. The results show that lime-crusted rammed earth technique and tower typologies are the most vulnerable structures while topography is somehow less important. The results suggest that for half of the structures analyzed for the given scenario the probabilities are above 80% for damage grade 4 and 5 (EMS-98). [ABSTRACT FROM AUTHOR]

Respirometric techniques were applied to estimate the toxic effect of several heavy metals (chromium(III), lead, nickel, mercury and zinc) on the activity of the heterotrophic bacteria present in activated sludge and to ascertain how the presence of these pollutants can affect biological treatment. For the assays, activated sludge was collected from the biological reactor (oxidation ditch) of a sewage treatment plant that also receives industrial wastewater. The tests were performed in a batch respirometer operating in dynamic mode, and the corresponding respirograms were obtained. The values obtained (between 0.47 and 0.71) for the specific growth yield coefficient in the different activated sludge samples pointed to the adequate performance of the biological treatment applied. The experimental data obtained showed that inhibition percentage is a logarithmic function of metal concentration, the toxicity of the heavy metals following the order: Hg ≫ Zn > Cr > Pb > Ni. [ABSTRACT FROM AUTHOR]

The aim of this research is to investigate the effect of phenyltriethoxysilane (PhTEOS) and tetraethoxysilane (TEOS) molar ratios as silicon precursors on the structure and porous texture of xerogels. We have prepared phenyl-silane hybrid xerogels from mixtures of PhTEOS and TEOS at pH 10 and 333 K, using ethanol as a solvent. Characterization techniques include 29Si NMR, FTIR, XRD, FE-SEM, HRTEM, TGA-DSC, helium density, and gas adsorption (N2 at 77 K and CO2 at 273 K). In order to assess the contribution of the quadrupolar moment of N2 and CO2 in the adsorption we obtained the adsorption–desorption isotherm of Ar at 87.3 K for the xerogel synthesized from 50% PhTEOS. The morphology of xerogels changed from aggregates of spherical particles for 20% PhTEOS to lamellae for samples obtained with PhTEOS percentages equal or larger that 60%. The incorporation of phenyl groups into the xerogel matrix caused an increase in the spacing bond between silicon atoms and led to an intramolecular reaction and the formation of lamellar domains. Increasing the PhTEOS molar ratio in the mixture of silicon precursors produced hybrid xerogels with lower specific surface area, pore volume and characteristic energy. The similarity between the isotherms of N2 at 77 K and Ar at 87.3 K indicates that the main retention mechanism is physisorption and that the variation in the surface chemistry with the incorporation of phenyl groups doesn't inhibit the retention of N2. [ABSTRACT FROM AUTHOR]

Electron tomography (ET) has rapidly developed into a powerful technique to characterize the three-dimensional (3D) structure of complex materials, with nanometer resolution, for a wide range of applications including heterogeneous catalysis. In these 3D studies, scanning transmission electron microscopy (STEM) has been the most widely used imaging mode, due to both its incoherent nature, which avoids the appearance of diffraction-related artefacts, and its sensitivity to composition, an important question for most catalytic systems. Though initially used as a qualitative tool to visualize 3D nanostructures, more recently STEM tomography is being also exploited to retrieve quantitative information in 3D. In this article, we review recent developments of STEM-based tomography for the understanding of heterogeneous catalysts at the nanometer level. The new possibilities opened by quantitative analysis will be illustrated by selected cases in which different parameters are calculated from 3D reconstructions and compared to their macroscopic measurements. The key influence of the latest developments in reconstruction and segmentation methods to assess reliability and accuracy in the quantification process is highlighted. [ABSTRACT FROM AUTHOR]

The present paper aims at presenting the methodology and first results of a detection system of risk of diabetic macular edema (DME) in fundus images. The system is based on the detection of retinal exudates (Ex), whose presence in the image is clinically used for an early diagnosis of the disease. To do so, the system applies digital image processing algorithms to the retinal image in order to obtain a set of candidate regions to be Ex, which are validated by means of feature extraction and supervised classification techniques. The diagnoses provided by the system on 1058 retinographies of 529 diabetic patients at risk of having DME show that the system can operate at a level of sensitivity comparable to that of ophthalmological specialists: it achieved 0.9000 sensitivity per patient against 0.7733, 0.9133 and 0.9000 of several specialists, where the false negatives were mild clinical cases of the disease. In addition, the level of specificity reached by the system was 0.6939, high enough to screen about 70% of the patients with no evidence of DME. These values show that the system fulfils the requirements for its possible integration into a complete diabetic retinopathy pre-screening tool for the automated management of patients within a screening programme. Graphical Abstract Diagnosis system of risk of diabetic macular edema (DME) based on exudate (Ex) detection in fundus images. [ABSTRACT FROM AUTHOR]

Tetraethoxysilane (TEOS) is widely used to synthesize siliceous material by the sol-gel process. However, there is still some disagreement about the nature of the limiting step in the hydrolysis and condensation reactions. The goal of this research was to measure the variation in the concentration of intermediates formed in the acid-catalyzed hydrolysis by 29Si NMR spectroscopy, to model the reactions, and to obtain the rate constants and the activation energy for the hydrolysis and early condensation steps. We studied the kinetics of TEOS between pH 3.8 and 4.4, and four temperature values in the range of 277.2-313.2 K, with a TEOS:ethanol:water molar ratio of 1:30:20. Both hydrolysis and the condensation rate speeded up with the temperature and the concentration of oxonium ions. The kinetic constants for hydrolysis reactions increased in each step kh1 < kh2 < kh3 < kh4, but the condensation rate was lower for dimer formation than for the formation of the fully hydrolyzed Si(OH)4. The system was described according to 13 parameters: six of them for the kinetic constants estimated at 298.2 K, six to the activation energies, and one to the equilibrium constant for the fourth hydrolysis. The mathematical model shows a steady increase in the activation energy from 34.5 kJ mol−1 for the first hydrolysis to 39.2 kJ mol−1 in the last step. The activation energy for the condensation reaction from Si(OH)4 was ca. 10 kJ mol−1 higher than the largest activation energy in the hydrolytic reactions. The decrease in the net positive charge on the Si atom contributes to the protonation of the ethoxy group and makes it a better leaving group. [ABSTRACT FROM AUTHOR]

The evolutionary history of the genus Ruppia has been shaped by hybridization, polyploidisation and vicariance that have resulted in a problematic taxonomy. Recent studies provided insight into species circumscription, organelle take-over by hybridization, and revealed the importance of verifying species identification to avoid distorting effects of mixing different species, when estimating population connectivity. In the present study, we use microsatellite markers to determine population diversity and connectivity patterns in Ruppia cirrhosa including two spatial scales: (1) from the Atlantic Iberian coastline in Portugal to the Siculo-Tunisian Strait in Sicily and (2) within the Iberian Peninsula comprising the Atlantic-Mediterranean transition. The higher diversity in the Mediterranean Sea suggests that populations have had longer persistence there, suggesting a possible origin and/or refugial area for the species. The high genotypic diversities highlight the importance of sexual reproduction for survival and maintenance of populations. Results revealed a regional population structure matching a continent-island model, with strong genetic isolation and low gene flow between populations. This population structure could be maintained by waterbirds, acting as occasional dispersal vectors. This information elucidates ecological strategies of brackish plant species in coastal lagoons, suggesting mechanisms used by this species to colonize new isolated habitats and dominate brackish aquatic macrophyte systems, yet maintaining strong genetic structure suggestive of very low dispersal. [ABSTRACT FROM AUTHOR]

An efficient exploitation of Distributed Computing Infrastructures (DCIs) is needed to deal with the data deluge that the scientific community is facing, in particular the Astrophysics one due to the emerging Square Kilometre Array (SKA) telescope that will reach data rates in the exascale domain. Hence, Science Gateways are being enriched with advanced tools that not only enable the scientists to build their experiments but also to optimize their adaptation to different infrastructures. In this work we present a method, called 'two-level workflow system', to build this kind of tools and we apply it to a set of analysis tasks of interest for some use applications to the SKA. This method uses the Software-as-a-Service model to keep the scientists insulated from technical complexity of DCIs, and the COMPSs programming model to achieve an efficient use of the computing resources. [ABSTRACT FROM AUTHOR]

Detection and quantification of cocaine is a key tool in fields such as police apprehensions and the fight against drug trafficking. Thus, a simple, fast and inexpensive electroanalytical methodology for the determination of cocaine in seized street samples has been developed, employing linear sweep voltammetry. The method is based on the use of a glassy carbon (GC) electrode modified by a combination of multi-walled carbon nanotubes (MWCNT) with β-cyclodextrin (β-CD) incorporated in a polyaniline film. The proposed method shows high reproducibility, repeatability and specificity. Under optimal conditions, the β-CD/MWCNT-modified GC electrode gives a detection limit of 1.02 μM cocaine. The results obtained are in good agreement with those obtained by the high-performance liquid chromatography reference method. The new methodology proposed has excellent potential as the basis of a portable analytical sensor for on-site screening of cocaine in seized street samples. [ABSTRACT FROM AUTHOR]

The development and application of a polyaniline/carbon nanotube (CNT) cyclodextrin matrix (PANI-β-CD/MWCNT)-based electrochemical sensor for the quantitative determination of the herbicide 4-chloro-2-methylphenoxyacetic acid (MCPA) and its main transformation product 4-chloro-2-methylphenol in natural waters are described. A simple cyclic voltammetry-based electrochemical methodology, in phosphate buffer solution at pH 6.0, was used to develop a method to determine both MCPA and 4-chloro-2-methylphenol, without any previous extraction or derivatization steps. A linear concentration range (10 to 50 μmol L) and detection limits of 1.1 and 1.9 μmol L, respectively, were achieved using optimized cyclic voltammetric parameters. The proposed method was successfully applied to the determination of MCPA and 4-chloro-2-methylphenol in natural water samples with satisfactory recoveries (94 to 107 %) and in good agreement with the results obtained by an established high-performance liquid chromatography technique, no significant differences being found between the methods. Interferences from ionic species and other herbicides used for broad-leaf weed control were shown to be small. The newly developed methodology was also successfully applied to MCPA photodegradation environmental studies. [ABSTRACT FROM AUTHOR]

The current study reports on the preparation of ~10–13 nm ZnO nanoparticles homogeneously doped with Fe 2+ ions ((Zn 0.97Fe 0.03)O) and the manipulation of their ferromagnetic response at room temperature with an appropriate post-processing. The homogeneous spatial distribution of iron is studied at atomic column level through high-resolution transmission electron microscopy, high-angle annular dark field, and electron energy loss spectroscopy. Magnetization isotherms show a ferromagnetic feature within the low field region exhibiting temperature dependence. X-ray diffraction and analytical microscopy measurements are compatible with a homogeneous distribution of Fe 2+ over the ZnO lattice, and discard the formation of iron or iron oxide clusters that could account for the low field ferromagnetic signal. From the temperature dependence of the susceptibility, it is inferred that Fe 2+ cations do not order magnetically. Induced defects upon calcination of different organic molecules over the (Zn 0.97Fe 0.03)O nanoparticles in aerobic conditions lead to a significant modification of the magnetic properties, even suppressing the room temperature ferromagnetic signal originally observed. More specifically, when the heat treatment is carried out in the presence of dodecylamine, the original room temperature ferromagnetic signal is canceled, whereas an enhancement on the same ferromagnetic contribution is observed when using trioctylphosphine oxide. No significant differences have been found after calcinating 1-dodecanethiol-doped ZnO nanoparticles. [ABSTRACT FROM AUTHOR]

Dissemination of knowledge in genetics to be applied in medicine has created a growing need for capacity building in health care workers. The CAPABILITY ARGENTINA outreach project protocol was designed as a model to introduce genetics in areas without genetic services. Our aim was for genetic health care to become part of primary care in an Argentine province lacking genetic services. The program was innovative as professionals from the referral center (Garrahan Hospital S.A.M.I.C.) traveled to remote areas to train professionals through problem-based education. A logical framework was designed for a local needs assessment. Teaching materials (Powerpoint presentations, printed syllabus, and CD) and a web page were developed. A demonstration project was carried out in the Province of Chaco, Argentina. A total of 485 health workers were trained. The number of consultations increased significantly in participating areas comparing before and after the training period. To support this increase, a complementary project was set up from a public hospital sponsored from within Argentina to build a cytogenetic laboratory in the capital of the Province of Chaco. The model was improved for reproduction in other areas in Argentina. CAPABILITY ARGENTINA is a capacity building model for training of primary care professionals in genetics that may be applied to other medical specialties. The outcomes of the programme have a direct impact on clinical practice. [ABSTRACT FROM AUTHOR]

Background and aims: The Tehuacán-Cuitcatlán reserve is an area of unique plant biodiversity mostly in the form of xerophytes, with exceptionally high numbers of rare and endemic species. This endemism results partly from the characteristics of the climate of this area, with two distinct seasons: rainy and dry seasons. Although rhizosphere communities must be critical in the function of this ecosystem, understanding the structure of these communities is currently limited. This is the first molecular study of the microbial diversity present in the rhizosphere of Mamillaria carnea. Methods: Total DNA was obtained from soil and rhizosphere samples at three locations in the Tehuacán Cuicatlán Reserve, during dry and rainy seasons. Temperature gradient gel electrophoresisis (TGGE) fingerprinting, 16S rRNA gene libraries and pyrosequencing were used to investigate bacterial diversity in the rhizosphere of Mammillaria carnea and changes in the microbial community between seasons. Results: Deep sequencing data reveal a higher level of biodiversity in the dry season. Statistical analyses based on these data indicates that the composition of the bacterial community differed between both seasons affecting to members of the phyla Acidobacteria, Cyanobacteria, Gemmatimonadetes, Plantomycetes, Actinobacteria and Firmicutes. In addition, the depth of sequencing performed (>24,000 reads) enables detection of changes in the relative abundance of lower bacterial taxa (novel bacterial phylotypes) indicative of the increase of specific bacterial populations due to the season. Conclusions: This study states the basis of the bacterial diversity in the rhizosphere of cacti in semi-arid environments and it is a sequence-based demonstration of community shifts in different seasons. [ABSTRACT FROM AUTHOR]

Catalysts of palladium (1 wt%) deposited over silica SBA-15 supported LaMnFeO perovskite (with perovskite loading of 10, 30 and 40 wt%), characterized by several techniques (BET, SAXS, XRD, TPR) are tested in the combustion of methane. Bulk LaMnFeO with the corresponding supported Pd catalyst are also considered for comparison purpose. Dispersing LaMnFeO oxide over silica SBA-15 improves the activity of the supported palladium catalysts to an extent depending on the perovskite loading. After ageing at 600 °C for 14 h, Pd catalysts supported over SBA-15 loaded with 30 and 40 wt% of LaMnFeO, deactivate less as compared to Pd over bulk perovskite. Moreover, during catalytic tests carried out in the presence of 10 vol. ppm SO these catalysts exhibit better sulphur tolerance and higher regeneration capability as compared to the Pd/LaMnFeO. The superior performance of such catalysts is attributed to the good dispersion of the LaMnFeO over the SBA-15, with consequent increase of the perovskite surface area with respect to bulk perovskite. In addition, the porous structure of the silica contributes to a better stabilization of the active species against sintering and acts as a chemical sink during the catalyst exposure to SO. [ABSTRACT FROM AUTHOR]

A new method for determining the Peltier coefficient of thermoelectric devices has been developed. The Peltier coefficient has been evaluated by measuring the temperature distribution along the junction of two dissimilar materials X and Y. The energy balance has been used to link the Peltier coefficient with the hot and cold temperatures of the metallic blocks of a thermoelectric module (TEM), thus enabling the evaluation of this coefficient. Data on the thermal conductance of the pellets are also needed. The experimental device used in this paper is a TEM composed of N = 71 couples of bismuth telluride, suitably doped to provide individual n and p elements. Using nominal values given by the manufacturer for the Seebeck coefficient of the TEM, the Onsager reciprocal relation has been confirmed. [ABSTRACT FROM AUTHOR]

The nature reserve of Tehuacan-Cuicatlan in central Mexico is known for its diversity and endemism mainly in cactus plants. Although the xerophytic flora is reasonably documented, the bacterial communities associated with these species have been largely neglected. We assessed the diversity and composition of bacterial communities in bulk (non-rhizospheric) soil and the rhizosphere of three cactus plant species: Mammillaria carnea, Opuntia pilifera and Stenocereus stellatus, approached using cultivation and molecular techniques, considering the possible effect of dry and rainy seasons. Cultivation-dependent methods were focused on putative N-fixers and heterotrophic aerobic bacteria, in the two media tested the values obtained for dry season samples grouped together regardless of the sample type (rhizospheric or non-rhizospheric), these groups also included the non-rhizospheric sample for rainy season, on each medium. These CFU values were smaller and significantly different from those obtained on rhizospheric samples from rainy season. Genera composition among isolates of the rhizospheric samples was very similar for each season, the most abundant taxa being α-Proteobacteria, Actinobacteria and Firmicutes. Interestingly, the genus Ochrobactrum was highly represented among rhizospheric samples, when cultured in N-free medium. The structure of the bacterial communities was approached with molecular techniques targeting partial 16S rRNA sequences such as denaturing gradient gel electrophoresis and serial analysis of ribosomal sequence tags. Under these approaches, the most represented bacterial phyla were Actinobacteria, Proteobacteria and Acidobacteria. The first two were also highly represented when using isolation techniques. [ABSTRACT FROM AUTHOR]

Wild carnivores are at the top of the trophic chain. They are predators and carrion consumers, and thus, prone to come in contact with disease agents contaminating the environment or infecting live or dead animals. We hypothesized that wild canids could be used as sentinels for the detection of regions with higher Mycobacterium avium paratuberculosis (MAP) prevalence in wild and domestic animals. To test this hypothesis, we set up an ELISA to test 262 wolf ( Canis lupus) and fox ( Vulpes vulpes) sera for MAP-specific antibodies and processed a subset of samples for culture ( n = 61), MAP-specific PCR (15) and histopathology (14). In wolves, the optical density (OD) values in the ELISA were continuously distributed. Ten fox sera (4%) had OD readings of over twice the mean, suggesting contact with mycobacteria. However, all samples tested by PCR were negative for both IS900 and ISMAP02 sequences, and samples cultured for MAP yielded no growth. No visible paratuberculosis or tuberculosis-compatible lesions were recorded. On histopathological examination, no lesions compatible with mycobacterial diseases were observed. These results suggest that wild canids show little or no evidence of paratuberculosis and are unlikely to be useful sentinels for the detection of MAP in Southwestern Europe. [ABSTRACT FROM AUTHOR]

Ninety percent of oesophageal cancers are locally advanced at diagnosis, and treatment yields discouraging results. High dose rate brachytherapy (HDR-BT) permits an increment of local doses without a significant increment of toxicity. The goal of our study is to compare different HDR-BT fractions and assess global survival (GS) and cause-specific survival (CSS). Twenty-six patients were treated for locally advanced oesophageal cancer with chemotherapy concomitant with conformal three-dimensional radiotherapy (C3DR) from January 1994 to December 2000. Of this group, 96.2% were males, mean age 63.08 years; the most frequent location was medium third, for 50% of cases. Eighty-four percent of cases were G2-3 epidermoid carcinomas. The administration consisted of 44.2 Gy with C3DR and 5 applications of HDR-BT of 500 cGy each. Actuarial GS and CSS at 5 years is 10.18% and 12.96%, a mean survival of 25.68 and 29.14 months respectively. The following factors (C3DR total dose, fraction dose and total dose of HDR-BT, number of applications, active length of application, total dose of C3DR plus HDR-BT, and BED of HDR-BT) are evaluated to find if they have an influence on treatment response, GS and actuarial CSS. The only result that yields statistical significance, in univariant analysis, is the active length in HDR-BT, thus for a greater active length of application, a minor response is obtained and GS diminishes ( p=0.05). We grouped BT fractions on biological equivalent dose (BED) into: <28, 28–33 and >33 Gy; mean survival and GS at 5 years increases with BED≥28 Gy ( p=0.016). Tumour response increases (complete and partial) when BED on HDR-BT is increased, regardless of the fraction employed. A BED higher than 28 Gy yields a significant increase of mean survival and GS at 5 years ( p=0.016). [ABSTRACT FROM AUTHOR]

The major protein constituent of amyloid deposits in Alzheimer's disease (AD) is the amyloid β-peptide (Aβ). In the present work, we have determined the effect of hyperforin an acylphloroglucinol compound isolated from Hypericum perforatum (St John's Wort), on Aβ-induced spatial memory impairments and on Aβ neurotoxicity. We report here that hyperforin: (1) decreases amyloid deposit formation in rats injected with amyloid fibrils in the hippocampus; (2) decreases the neuropathological changes and behavioral impairments in a rat model of amyloidosis; (3) prevents Aβ-induced neurotoxicity in hippocampal neurons both from amyloid fibrils and Aβ oligomers, avoiding the increase in reactive oxidative species associated with amyloid toxicity. Both effects could be explained by the capacity of hyperforin to disaggregate amyloid deposits in a dose and time-dependent manner and to decrease Aβ aggregation and amyloid formation. Altogether these evidences suggest that hyperforin may be useful to decrease amyloid burden and toxicity in AD patients, and may be a putative therapeutic agent to fight the disease.Molecular Psychiatry (2006) 11, 1032–1048. doi:10.1038/sj.mp.4001866; published online 25 July 2006 [ABSTRACT FROM AUTHOR]

Alzheimer's disease (AD) is a progressive neurodegenerative disorder, which is probably caused by the cytotoxic effect of the amyloid β-peptide (Aβ ). We report here molecular changes induced by Aβ, both in neuronal cells in culture and in rats injected in the dorsal hippocampus with preformed Aβ fibrils, as an in vivo model of the disease. Results indicate that in both systems, Aβ neurotoxicity resulted in the destabilization of endogenous levels of β-catenin, a key transducer of the Wnt signaling pathway. Lithium chloride, which mimics Wnt signaling by inhibiting glycogen synthase kinase-3β promoted the survival of post-mitotic neurons against Aβ neurotoxicity and recovered cytosolic β-catenin to control levels. Moreover, the neurotoxic effect of Aβ fibrils was also modulated with protein kinase C agonists/inhibitors and reversed with conditioned medium containing the Wnt-3a ligand. We also examined the spatial memory performance of rats injected with preformed Aβ fibrils in the Morris water maze paradigm, and found that chronic lithium treatment protected neurodegeneration by rescuing β-catenin levels and improved the deficit in spatial learning induced by Aβ. Our results are consistent with the idea that Aβ-dependent neurotoxicity induces a loss of function of Wnt signaling components and indicate that lithium or compounds that mimic this signaling cascade may be putative candidates for therapeutic intervention in Alzheimer's patients. [ABSTRACT FROM AUTHOR]

The objective of this study was to compare, at equal blood pressure (BP) reduction, the effect of two different combinations on metabolic control and albuminuria in type 2 diabetic hypertensive patients with albuminuria. This was a prospective, randomised, double-blind, parallel, controlled trial carried out in 11 Spanish hospitals. A total of 103 type 2 diabetic patients with stable albuminuria and BP not controlled on monotherapy were randomised of which 93 finished the study. After a 4-week single-blind placebo period, patients were randomised to verapamil SR/trandolapril 180/2 mg (VT) or to enalapril/hydroclorothiazide 20/12.5 mg (EH). Treatment duration was 6 months. The main outcome measures were changes in BP, 24-h albuminuria, blood glucose and glycated haemoglobin. Overall BP was significantly reduced from 157.3 ± 12.0/98.3 ± 6.4 mm Hg to 140.5 ± 14.5/86.1 ± 8.2 mm Hg (P < 0.001) and albuminuria significantly decreased from 508.6 ± 693.8 mg/24 h to 253.4 ± 517.2 mg/24 h (P < 0.001), both without significant differences between treatments. Glycated haemoglobin was not modified on VT: baseline, 5.91 ± 1.43%; end of treatment, 5.94 ± 1.62%, but increased on EH: baseline, 5.96 ± 1.25%; final, 6.41 ± 1.51%, (ANOVA interaction P = 0.040). At the end of the study, a blood glucose 3126 mg/dL was attained in 72.7% of the VT group--improving in 29.5% and worsening in 6.8% of patients (P = 0.021)--and in 50% of the EH group, 13.6% of patients improved and 11.4% worsened (P = 1.000). There were no changes in body weight, serum creatinine, uric acid, potassium, cholesterol, tryglicerides and serum albumin. In hypertensive type 2 diabetic patients not controlled on monotherapy, both treatments similarly reduced albuminuria. The combination verapamil/ trandolapril seems to allow a better metabolic control than enalapril/hydroclorothiazide. [ABSTRACT FROM AUTHOR]

RPHPLC methods for analysis of photosynthetic pigments (chlorophylls and carotenoids) usually require addition of water to methanol or acetone extracts to prevent distortion of early-eluting peaks corresponding to the more polar compounds. In this work we have investigated the short-(<2 min) and long-term (up to 48 h) effect of adding water to acetone and methanol extracts from two marine phytoplankton species, Emiliania hyxleyi and Dunaliella tertiolecta. Solvent extracts were prepared and separated into fractions that were subsequently diluted with water to 90%, 80%, 70%, 60%, 50%, and 40% for methanol, and the same range extended to 30% and 20% for acetone. Changes in pigment concentration with time were followed spectrophotometrically and chromatographically. Losses of pigments as a result of precipitation were clearly observed immediately after dilution of acetone extracts to 60% or less and methanol extracts to 80% or less. For chlorophyll a the most substantial losses were recorded for 50% acetone (up to 27% decrease) and for 70% methanol (31% decrease). This effect increased considerably with time. Only for 90% and 80% acetone were the initial concentrations of all the pigments unchanged after 24h, and even up to 48 h. In contrast, more than 60% and 57% of the initial amounts of chlorophyll a were lost after 24 h in 50% acetone and 70% methanol extracts, respectively. These losses increased to 83% and 60% after 48 h. There was a clear correlation between the polarity of a pigment and the polarity of the solvent at which maximum precipitation occurred. Losses of pigment from pure acetone and methanol extracts with time were also observed, although we attribute these to pigment degradation rather than precipitation. Some of the losses occurring with time can be avoided by use of autosamplers in which the sample can be mixed with water immediately before injection. [ABSTRACT FROM AUTHOR]

The Acknowledgements now reads "This work has been funded by the European Union's Horizon 2020 research and innovation program under Grant Agreement No. 732032 (BrainCom) and Graphene Flagship Grant Agreements No. 785219 (GrapheneCore2) and 881603 (GrapheneCore3). The original version of this article included an incorrectly named funding source "Graphene Flagship", and omitted the names of GrapheneCore 2 and GrapheneCore3 as funding sources, from the Acknowledgements. [Extracted from the article]

The separation of mono- and divinyl chlorophyll c forms was estudied employing several octylsilica and octadecylsilica columns under isocratic conditions. In this paper we show that, using the adequate mobile phases, the monomeric C8 columns can separate the mentioned chlorophylls. A comparison between C8 and C18 columns reveals that monomeric OS phases provide always higher resolution of the MV- and DV chlorophyll c pairs. Such a result could be explained in terms of differences in column polarity. When adequate gradient profiles and injection conditions are used the separation is accomplished together with that of other chlorophylls and carotenoids. [ABSTRACT FROM AUTHOR]

We report the use of ECR plasma to grow and deposit silicon oxides ranged between 2.5 and 10 nm with rates between 0.04 and 2.0 nm s−1. The thickness of the films, well grown or deposited, were characterized by means of a spectroscopic ellipsometer, operating in the 1.5–4.5 eV range. Uniformities of thin oxide films were better than 4% on 3″ silicon wafers, and ranged from 4% to 6% between different runs. The concentrations of the different chemical species during the first stages of the plasma formation were followed by optical emission spectroscopy to give some insight into the origin of the properties of the different thin SiO x films. FT-IR spectra show bands with larger FWHM in ECR oxides than in the thermal ones, but the main peak positions were close to one another in the spectra of the three kinds of oxides. The observed mode strength for the LO4-TO4 pair of each spectrum is the main aspect that distinguishes the deposited from the grown film, indicating unequal degrees of disorder in both oxides. C–V measurements were performed in MOS capacitors. In the as-deposited SiO x films a positive net oxide charge density similar to the one in the thermal SiO2 films is observed. It is worth noting that a post-metallization anneal causes a reduction of the initial net charge density and even a sign change, depending on the treatment conditions. [ABSTRACT FROM AUTHOR]

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The separation of chlorophyll forms was studied employing a wide bore polymeric octadecylsilica column and pyridine containing mobile phases, giving consideration to considering the influence of mobile phase composition and column temperature on the resolution of monovinyl forms from their divinyl analogues. A method involving gradient elution and operating at 15°C is proposed for the separation of several polar and non-polar mono- and divinyl chlorophylls from etiolated tissues of higher plants and from marine phytoplankton. The advantages of pyridine as a mobile phase additive in the reversed-phase liquid chromatography of chlorophylls are discussed. [ABSTRACT FROM AUTHOR]

The effect of inoculation with the saprophytic fungi Alternaria alternata or Fusarium equiseti on maize ( Zea mays) and lettuce ( Lactuca sativa) with or without arbuscular mycorrhizal (AM) colonization by Glomus mosseae was studied in a greenhouse trial. Plant dry weights of non-AM-inoculated maize and lettuce were unaffected by the presence of A. alternata and F. equiseti. In contrast, A. alternata and F. equiseti decreased plant dry weights and mycorrhization when inoculated to the rhizosphere before G. mosseae. The saprophytic fungi inoculated 2 weeks after G. mosseae did not affect the percentage of root length colonized by the AM endophyte, but did affect its metabolic activity assessed as succinate dehydrogenase activity. Although F. equiseti inoculated at the same time as G. mosseae did not affect mycorrhization of maize roots, its effect on AM colonization of lettuce roots was similar to that with A. alternata. In the rhizosphere of both plants, the population of saprophytic fungi decreased significantly, but was not affected by the presence of G. mosseae. Our results suggest that there may have been a direct effect of the saprophytic fungi on the mycorrhizal fungi in the extramatrical phase of the latter, and when the AM fungus was established in the root the AM fungus was less affected by the saprophytic fungi. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the influence of verapamil SR 240 mg (V) and the combination amiloride 5 mg + hydrochlorothiazide 50 mg (AH) on diastolic dysfunction of hypertensive patients without left ventricular hypertrophy (LVH). Twenty-six hypertensive patients with diastolic dysfunction, normal systolic function and without LVH were included into a 2-week washout period and then randomised to a 6-month V or AH treatment. One blinded-to-treatment echocardiographist at baseline and at weeks 4, 12 and 24 assessed Doppler-echocardiography. Both V and AH, satisfactorily controlled blood pressure, but only V improved diastolic function shown by a tendency to reduce peak A and to increase peak E/A ratio, and by a significant reduction in deceleration time. After 24 weeks, V significantly reduced wall thickness in comparison with AH. These results need to be confirmed in a larger scale study. [ABSTRACT FROM AUTHOR]

Temperature profile evolutions produced by a scanning electron beam in crystalline silicon have been numerically calculated using a two-dimensional finite-element scheme. The temperature dependence of the different silicon properties as well as the electron penetration effects have been taken into account. Numerical calculations carried out at different conditions have been compared with experimental melting-threshold measurements using an electron beam with a Gaussian power density distribution. The good agreement between numerical calculations and experimental results proves the validity of the two-dimensional approach. [ABSTRACT FROM AUTHOR]

The recrystallization kinetics of BF ion-implanted silicon has been studied by means of spectroscopic ellipsometry. It has been found that the dielectric constant of the implanted layers depends on the energy, dose and ion-beam current. The activation energy of the regrowth process increases with ion peak concentration becoming saturated for the largest implanted doses. In the largest-dose samples implanted at low current a significant decrease of the regrowth rate was detected when the recrystallization front crosses the peak of the impurity distribution. [ABSTRACT FROM AUTHOR]

The aim of this study was to show the US findings in mode B and color Doppler duplex of the dilatation of the rete testis, in order to analyze its association with other scrotal processes and to confirm their inclusion into the benign testicular lesions. We present seven diagnosed cases (mean age 61 years) of dilatation of the rete testis to which a clinical control and US was accomplished up to 1 year. The scrotal sonography study was carried out with a linear probe of 7.5 Mhz. In the US examination we observed in all cases an intratesticular image located in the mediastinum testis constituted by anechoic and serpiginous tubular structures, which do not show any blood flow with the color Doppler. In one case the mentioned observations were bilateral. Five cases had cysts in epididymis and the last case showed an increase in size in the epididymis head. Color Doppler duplex examination did not detected flow dots in the seven patients. The dilatation of the rete testis is a benign entity frequently associated with pathology in epididymis, with specific US findings which permit avoidance of invasive tests. [ABSTRACT FROM AUTHOR]

We studied changes in gene expression during the establishment of vesicular-arbuscular (VA) mycorrhizal symbiosis. Polypeptides were obtained by in vitro translation of total root RNA extracted from VA-colonized and noncolonized root-tissue of onion ( Allium cepa L. cv. Babosa), and resolved by two-dimensional polyacrylamide gel electrophoresis. VA mycorrhization led to a specific appearance of eight new polypeptides, and the disappearance of seven polypeptides in VA-colonized root. Our findings indicate that gene expression is altered in response to morphological and physiological changes resulting from the establishment of VA mycorrhizas. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to an article on predisposing factors for urgent colectomy in patients with ulcerative colitis (UC) that was published in one of the previous issues.

Reports on coprophagy in Egyptian vulture 'Neophron percnopterus' and how it acts as a source of carotenoids in vertebrates. Reasons for which coprophagy is dangerous for vertebrates; Chromatographic analysis of carotenoid content of ungulate feces Plasma carotenoid content in vultures inhabiting greener pastures; Plasma lurein content in vultures in a trial during which they were fed with ungulate feces.