5,754 research outputs found

    Effects of inoculum type, packing material and operating conditions on pentane biofiltration

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    Biofilters are an interesting alternative to treat airstreams polluted with gaseous alkanes from industrial activities. These hydrophobic compounds are difficult to treat by bacterial communities which are generally used in biofiltration. In this work, four fungal populations (3 consortia and Fusarium solani) were used as inocula in biofilters for treating pentane and hexane. The biofilters were packed with inorganic and organic materials (perlite and peat) and operated with the periodic addition of mineral medium at pH 4 supplemented with antibacterial agents to favor the development of fungi. To reduce the lag phase, the biofilters were inoculated with active mycelia. Lower performance was obtained with the peat biofilters. Sustained 100 % removal efficiencies were obtained with biofilters at an operation pentane load of = 32.9 ± 8.1 g m-3 h-1. Maximum elimination capacity of Cmax = 100 g m-3 h-1 was obtained with one of the fungal consortia; this value is higher than those usually reported for pentane degrading bacterial biofilters

    Holocene humidity changes in southern Iberia inferred from the geochemical signature of marine sediments

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    The Mediterranean region is particularly sensitive to global climate variability that critically reflects on its hydrological conditions. A recently published high resolution reconstruction of Holocene Sea Surface Temperature (SST) based on Globigerina bulloides Mg/Ca ratios, set the basis to explore, within a warm climatic period, the impact of North Atlantic oceanographic conditions shaping the properties of the inflowing waters into the Mediterranean Sea. Here we go a step further in establishing the potential links between these oceanographical changes with the hydrological conditions on the southern Iberian Peninsula.This study combines XRF-core-scanner analyses with the radiogenic isotopes characterization (Sr, Nd and Pb) of the terrigenous fraction in core ALB-2 from the Alboran Sea. Results indicate that the most humid conditions developed during the early to middle Holocene with a transition towards drier conditions and colder SST that occurred by the late Holocene. The radiogenic Sr, Nd and Pb records do not show any covariance with the millennial scale oscillations shown in the Zr and K XRF records interpreted as humidity changes. This could suggest that inputs of African dust are not the main controlling factor in the XRF records. In contrast, the Sr isotope record shows a significant transition around the middle Holocene while SSTs show a cooling trend. For an accurate interpretation of that feature, this study also targets a novel approach by characterizing the radiogenic isotope composition of settling particles recovered by moored sediment traps under well characterized meteorological conditions

    Eastern Mediterranean water outflow during the Younger Dryas was twice that of the present day

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    Eastern Mediterranean deep-intermediate convection was highly sensitive to varying inputs of fresh water fluxes associated with increased rainfall during the African Humid period (15-6 kyr Before Present). Here we investigate changes in the water-outflow from the Eastern Mediterranean Sea since the last deglaciation using neodymium isotope ratios. Our results indicate enhanced outflow during the Younger Dryas, two times higher than present-day outflow and about three times higher than during the last Sapropel. We propose that the increased outflow into the western Mediterranean over the Younger Dryas was the result of the combined effect of 1) enhanced climate-driven convection in the Aegean Sea and 2) reduced convection of western deep water during this period. Our results provide solid evidence for an enhanced Younger Dryas westward flow of Eastern Mediterranean sourced waters in consonance with an intensification of Mediterranean water-outflow during a weakened state of the Atlantic circulatio

    Micro and nano-patterning of single-crystal diamond by swift heavy ion irradiation

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    This paper presents experimental data and analysis of the structural damage caused by swift-heavy ion irradiation of single-crystal diamond. The patterned buried structural damage is shown to generate, via swelling, a mirror- pattern on the sample surface, which remains largely damage-free. While extensive results are available for light ion implantations, this effect is reported here for the first time in the heavy ion regime,where a completely different range of input parameters (in terms of ion species, energy, stopping power, etc.) is available for customized irradiation. The chosen ion species are Au and Br, in the energy range 10–40 MeV. The observed patterns, as characterized by profilometry and atomic force microscopy, are reported in a series ofmodel experiments,which show swelling patterns ranging from a few nm to above 200 nm. Moreover, a systematic phenomenological modeling is presented, inwhich surface swelling measurements are correlated to buried crystal damage. A comparison ismade with data for light ion implantations, showing good compatibilitywith the proposedmodels. The modeling presented in thiswork can be useful for the design and realization of micropatterned surfaces in single crystal diamond, allowing generating highly customized structures by combining appropriately chosen irradiation parameters and masks

    Métodos computacionales para estudio de la anemia drepanocítica

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    El procesamiento de imágenes digitales y la visión por computador son ampliamente utilizados en medicina actualmente y son de gran interés las propuestas de nuevos métodos de análisis automatizado de imágenes digitales o mejorar la eficiencia de los existentes. En este trabajo se desarrollaron métodos nuevos para estudiar computacionalmente a través de imágenes de muestras de sangre la drepanocitosis, dolencia con alta incidencia mundial y en Cuba, sobre todo en la región oriental. Se propusieron nuevos métodos de análisis de formas, obtenidos a partir de resultados clásicos de geometría integral y nuevas propuestas de visión por computador para evaluar trastornos neurofisiológicos asociados a través del estudio de las expresiones faciales del paciente. La validación estadística realizada comprobó la superioridad de estos métodos sobre otros, se determinó que son válidos para ser introducidos en software de apoyo para mejorar la calidad de la atención médica.Palabras clave: análisis de forma, análisis de expresiones faciales, drepanocitosis.</p

    Long-term precipitation in Southwestern Europe reveals no clear trend attributable to anthropogenic forcing

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    We present a long-term assessment of precipitation trends in Southwestern Europe (1850-2018) using data from multiple sources, including observations, gridded datasets and global climate model experiments. Contrary to previous investigations based on shorter records, we demonstrate, using new long-term, quality controlled precipitation series, the lack of statistically significant long-term decreasing trends in precipitation for the region. Rather, significant trends were mostly found for shorter periods, highlighting the prevalence of interdecadal and interannual variability at these time-scales. Global climate model outputs from three CMIP experiments are evaluated for periods concurrent with observations. Both the CMIP3 and CMIP5 ensembles show precipitation decline, with only CMIP6 showing agreement with long term trends in observations. However, for both CMIP3 and CMIP5 large interannual and internal variability among ensemble members makes it difficult to identify a trend that is statistically different from observations. Across both observations and models, our results make it difficult to associate any declining trends in precipitation in Southwestern Europe to anthropogenic forcing at this stage

    The Right to Code and Share Arms

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    Glycerol is, to date, the most widely used cryoprotectant to freeze stallion spermatozoa at concentrations between 2% and 5%. Cryoprotectant toxicity has been claimed to be the single most limiting factor for the success of cryopreservation. In order to evaluate the toxic effects of the concentrations of glycerol used in practice, stallion spermatozoa were incubated in Biggers Whitten and Whittingham (BWW) media supplemented with 0%, 0.5%, 1.5%, 2.5%, 3.5%, and 5% glycerol. In two additional experiments, a hyposmotic (75 mOsm/kg) and a hyperosmotic (900 mOsm/kg) control media were included. Sperm parameters evaluated included cell volume, membrane integrity, lipid peroxidation, caspase 3, 7, and 8 activation, mitochondrial membrane potential, and integrity of the cytoskeleton. Glycerol exerted toxicity at concentrations 3.5% and the maximal toxicity was observed at 5%. The actin cytoskeleton was especially sensitive to glycerol presence, inducing rapid F actin depolymerization at concentrations over 1.5%. The sperm membrane and the mitochondria were other structures affected. The toxicity of glycerol is apparently related to osmotic and nonosmotic effects. In view of our results the concentration of glycerol in the freezing media for stallion spermatozoa should not surpass 2.5%.Funding Agencies|Ministerio de Ciencia e Innovacion-FEDER Madrid, Spain|AGL 2010 20758 (GAN)|Inia|RZ2008-00018-00-00|Junta de Extremadura FEDER GR|10010

    Clinical Risk Score to Predict Pathogenic Genotypes in Patients With Dilated Cardiomyopathy

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    Background: Although genotyping allows family screening and influences risk-stratification in patients with nonischemic dilated cardiomyopathy (DCM) or isolated left ventricular systolic dysfunction (LVSD), its result is negative in a significant number of patients, limiting its widespread adoption. Objectives: This study sought to develop and externally validate a score that predicts the probability for a positive genetic test result (G+) in DCM/LVSD. Methods: Clinical, electrocardiogram, and echocardiographic variables were collected in 1,015 genotyped patients from Spain with DCM/LVSD. Multivariable logistic regression analysis was used to identify variables independently predicting G+, which were summed to create the Madrid Genotype Score. The external validation sample comprised 1,097 genotyped patients from the Maastricht and Trieste registries. Results: A G+ result was found in 377 (37%) and 289 (26%) patients from the derivation and validation cohorts, respectively. Independent predictors of a G+ result in the derivation cohort were: family history of DCM (OR: 2.29; 95% CI: 1.73-3.04; P &lt; 0.001), low electrocardiogram voltage in peripheral leads (OR: 3.61; 95% CI: 2.38-5.49; P &lt; 0.001), skeletal myopathy (OR: 3.42; 95% CI: 1.60-7.31; P = 0.001), absence of hypertension (OR: 2.28; 95% CI: 1.67-3.13; P &lt; 0.001), and absence of left bundle branch block (OR: 3.58; 95% CI: 2.57-5.01; P &lt; 0.001). A score containing these factors predicted a G+ result, ranging from 3% when all predictors were absent to 79% when ≥4 predictors were present. Internal validation provided a C-statistic of 0.74 (95% CI: 0.71-0.77) and a calibration slope of 0.94 (95% CI: 0.80-1.10). The C-statistic in the external validation cohort was 0.74 (95% CI: 0.71-0.78). Conclusions: The Madrid Genotype Score is an accurate tool to predict a G+ result in DCM/LVSD

    Management plan and surveillance monitoring for an urban lake in a coastal touristic town

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    Urban lakes have been created for different purposes, such as storing rainwater and avoiding flooding of adjacent urban areas. As an added value, they can be important recreational areas with an intrinsic aesthetic value. These artificial systems are characterised by very shallow waters, large amount of nutrient inputs and reduced water flow. These characteristics make them very prone to eutrophication process with the consequent deterioration of water quality and aesthetic value. The objective of this study is to present the management plan for a small urban lake (11,264 m2 and 1.5 m average depth) in Tavernes de la Valldigna (Valencia, Spain). This urban lake was constructed in a natural depression after the important flooding caused by the Júcar River overflow (15,000 m3/s peak flow) and the breaking of the Tous Dam in 1982. It works as storm tank and it has a pumping station to alleviate flow directly to the Mediterranean Sea. Around the lake, there is a recreational area that is mostly used in summer during touristic season. Since its construction it has suffered repeated events of fish deaths and bad odours that cause the alarm of residents and tourists. Municipal authorities worried by the environmental health risk and the economic impact on the tourism industry decided to undertake a restoration project. The results of this study present the initial status diagnosis and the propose d management plan. For guarantying the success of the implemented measures, a surveillance monitoring is designed.Sebastiá-Frasquet, M.; Sanchís Blay, JA.; Tormo-Flores, JB.; Altur Grau, VJ.; Pena-Regueiro, J. (2016). Management plan and surveillance monitoring for an urban lake in a coastal touristic town. International Journal of Sustainable Development and Planning. 11(6):886-896. doi:10.2495/SDP-V11-N6-886-896S88689611

    Models of Neutrino Masses and Mixings

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    We review theoretical ideas, problems and implications of neutrino masses and mixing angles. We give a general discussion of schemes with three light neutrinos. Several specific examples are analyzed in some detail, particularly those that can be embedded into grand unified theories.Comment: 44 pages, 2 figures, version accepted for publication on the Focus Issue on 'Neutrino Physics' edited by F.Halzen, M.Lindner and A. Suzuki, to be published in New Journal of Physics
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