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Macrophages are known to depict two major phenotypes: classically activated macrophages (M1), associated with high production of pro-inflammatory cytokines, and alternatively activated macrophages (M2), which present an anti-inflammatory function. A precise control over M1-M2 polarization is a promising strategy in therapeutics to modulate both tissue regeneration and tumor progression processes. However, this is not a simple task as macrophages behave differently depending on the microenvironment. In agreement with this, non-consistent data have been reported regarding macrophages response to magnetic iron oxide nanoparticles (MNPs). To investigate the impact of both tissue microenvironment and MNPs properties on the obtained macrophage responses, single-core (SC) and multi core (MC) citrate coated MNPs, are synthesized and, afterwards, loaded with a macrophage polarization trigger, IL-4. The developed MNPs are then tested in macrophages subjected to different stimuli. We demonstrate that macrophages treated with low concentrations of MNPs behave differently depending on the polarization stage independently of the concentration of iron. Moreover, we find out that MNPs size and morphology determines the effect of the IL-4 loaded MNPs on M1 macrophages, since IL-4 loaded SC MNPs favor the polarization of M1 macrophages towards M2 phenotype, while IL-4 loaded MC MNPs further stimulate the secretion of pro-inflammatory cytokines

Graphene oxide has been prepared from an industrial coke-like waste. The morphology of this material (GO-CW) is similar to that of standard graphene oxide (GO-G), although its surface has more defects. Both materials were used to prepare hybrid NHC-Ir(I)/graphene materials, consisting of molecular Ir(NHC) complexes covalently anchored to the graphene surface through the NHC moiety, following two different synthetic routes: (a) direct graphene electrografting of the previously synthesized aniline-functionalized imidazole-2-ylidene-Ir(I) complex, and (b) a two-step sequence comprising initial electrografting of aniline-imidazolium salts and subsequent chemical reaction with Ir(I) precursor anchoring imidazole-2-ylidene-Ir(I) molecular complexes. The synthesized NHC-Ir/graphene hybrid catalysts are active in the oxygen evolution reaction (OER) resulting in current densities in a similar range to those of other NHC-iridium(I) catalysts supported on GO. The highest activity corresponds to hybrid catalysts prepared by the two-step route, with even higher activity and stability when graphene oxide from industrial waste is used. EXAFS spectra of the materials prepared from both synthesis routes before oxidation catalysis reveal the local Ir coordination shell and a structural interaction between Ir and graphene. Both XANES and EXAFS spectra after electrocatalysis point to more oxidized species in which the molecular nature of the iridium catalysts is preserved.

The filamentous cyanobacterium Limnospira platensis, formerly known as Arthrospira platensis or spirulina, is one of the most commercially important species of microalgae. Due to its high nutritional value, pharmacological and industrial applications it is extensively cultivated on a large commercial scale. Despite its widespread use, its precise manipulation is still under development due to the lack of effective genetic protocols. Genetic transformation of Limnospira has been attempted but the methods reported have not been generally reproducible in other laboratories. Knowledge of the transformation defense mechanisms is essential for understanding its physiology and for broadening their applications. With the aim to understand more about the genetic defenses of L. platensis, in this work we have identified the restriction-modification and CRISPR-Cas systems and we have cloned and characterized thirteen methylases. In parallel, we have also characterized the methylome and orphan methyltransferases using genome-wide analysis of DNA methylation patterns and RNA-seq. The identification and characterization of these enzymes will be a valuable resource to know how this strain avoids being genetically manipulated and for further genomics studies.

An important part of the ecological evolution of many lineages consists of adaptations to new diets as climate and available resources changed. In this study, we inferred when squirrels adapted morphologically to new diets by analyzing data from both extant and extinct species. We relied on the relationship between tooth morphology in extant squirrels and their dietary preferences to infer the diets of extinct species. To achieve this, we employed two approaches, namely geometric morphometrics and Elliptic Fourier analyses, to measure the outline of the fourth lower premolar (p4) in occlusal view. We then used both datasets to infer the diets of extinct species. Additionally, we used phylogenetic comparative methods on extant data to explore the evolution of diet and tooth size, identifying potential drivers of squirrel morphological evolution in the context of past climatic changes. Our findings indicate that the morphology of squirrel teeth has been maintained through the evolutionary history of most lineages, but that it also has changed in some lineages as a result of adaptations to particularly demanding diets, sometimes mediated by climatic factors, which have played a crucial role in shaping tooth morphology. Furthermore, we demonstrated that both geometric morphometrics and Elliptic Fourier analyses can yield a similar percentage of correct classifications and congruent dietary inferences. This study provides valuable insights into the macroevolutionary changes in squirrels and provides further evidence of the usefulness of tooth morphology for inferring the diets of extinct mammalian species.

An important part of the ecological evolution of many lineages consists of adaptations to new diets as climate and available resources changed. In this study, we inferred when squirrels adapted morphologically to new diets by analyzing data from both extant and extinct species. We relied on the relationship between tooth morphology in extant squirrels and their dietary preferences to infer the diets of extinct species. To achieve this, we employed two approaches, namely geometric morphometrics and Elliptic Fourier analyses, to measure the outline of the fourth lower premolar (p4) in occlusal view. We then used both datasets to infer the diets of extinct species. Additionally, we used phylogenetic comparative methods on extant data to explore the evolution of diet and tooth size, identifying potential drivers of squirrel morphological evolution in the context of past climatic changes. Our findings indicate that the morphology of squirrel teeth has been maintained through the evolutionary history of most lineages, but that it also has changed in some lineages as a result of adaptations to particularly demanding diets, sometimes mediated by climatic factors, which have played a crucial role in shaping tooth morphology. Furthermore, we demonstrated that both geometric morphometrics and Elliptic Fourier analyses can yield a similar percentage of correct classifications and congruent dietary inferences. This study provides valuable insights into the macroevolutionary changes in squirrels and provides further evidence of the usefulness of tooth morphology for inferring the diets of extinct mammalian species., Universidad Complutense de Madrid, American Museum of Natural History, Alexander von Humboldt Foundation, MCIN/AEI/10.13039/501100011033, European Union Next Generation EU/PRTR, Ministerio de Ciencia, Innovación y Universidades-Agencia Estatal de Investigación, Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

This work describes a novel route for the preparation of pitches by oxidative polymerization of an industrial anthracene oil (AO) in a microwave semi-pilot equipment consisting in a multi-mode applicator having a 2.45 GHz magnetron with variable microwave power. The experimental five variables of microwave heating of AO air-blowing range between 320 and 380 °C (temperature), 0.2–3.9 °C min−1 (heating rate), 1.5–5 h (soaking time), 16–20.5% (air/AO ratio) and 200–1500 g (initial weight). Their effect on the overall microwave air-blowing process is evaluated by means of a statistical analysis. A detailed characterization of the pitches has been carried out in terms of ultimate analysis, softening point, solubility parameters (toluene insolubles (TI) and quinoline insolubles (QI)) and thermogravimetric analysis. The experiments were also carried out by using conventional heating for comparative purposes. The detailed study of the electric energy consumption of the overall microwave treatment allows estimating a significant electric energy saving of about 20% when compared to conventional heating thus representing an excellent result in the production of carbon precursors.

The effect of the structural properties of graphene materials on the local structure of –OH anchored Ir(I)–NHC complexes is herein investigated. For that, two partially reduced graphene oxides exhibiting different sheet properties due to an adequate selection of the crystalline characteristics of their parent graphite were used. The main differences among them were the size of Csp2 domains within their graphenic layers and the distribution of functional groups at the basal planes and edges. Anchoring of N-methylimidazolium moieties through the graphene –OH functional groups and subsequent formation of the Ir(I)–NHC complexes resulted in graphene-based hybrid materials. The structural differences of the support have an influence in the interaction of the supported iridium compounds with the graphene sheet. The oxygenated functional groups in the material with a smaller graphene sheet are closer leaving larger Csp2 domains in the graphene layer, favoring their interaction with the supported iridium atoms therefore displacing the chlorido ligand from the first coordination shell. In contrast, the hybrid material in which the distribution of the oxygenated functional groups within the basal planes of the graphenic layer is more homogeneous shows partial chlorido displacement. This fact has an influence on the electrocatalytic performance of the iridium-based hybrid materials as water oxidation catalysts (WOCs), exhibiting improved catalytic activity the catalyst having coordinated chlorido ligands.

In this article, a zooarchaeological and isotopic analysis is presented for 26 dog exemplars (Canis familiaris). These dogs were deposited in burial and ceremonial structures in the northeastern Iberian Peninsula during the Middle Neolithic, within the Pit Grave cultural horizon (ca. 4200–3600 cal BC). Four archaeological sites of the Catalonian coastal strip are studied: Camí de Can Grau, La Serreta, Ca l'Arnella, and Bòbila Madurell (one of the most important necropolises of the Iberian Peninsula). The presence of these dogs is interpreted as evidence of accompanying offerings and represents the most ancient use of this animal in the context of burials within the studied territory. Although it is a not a globally recorded gesture during this period, in light of the present results, it can be considered as a stereotyped ritual activity and evidence of the close relationship between these animals and the human communities. The diet of most of the dogs must be considered mixed and very similar to that of the humans, including consumption of herbivores and terrestrial plants.

N-enriched activated carbon fibers were successfully prepared from a coal derived pitch blended with urea-formaldehyde resin. The mixture was melt-spun, stabilized, carbonized and activated with KOH, giving rise to microporous carbon fibers with high nitrogen content (up to 2.2%). Nitrogen functional groups were mostly identified as quaternary N, and the content in this nitrogen group decreased with the degree of activation. N-enriched fibers activated under mild conditions (KOH/fiber = 5/1) showed the highest CO2 uptake (3.4 mmol CO2 g-1 at 25 °C and 1 atm). Due to their high alkalinity, the N-enriched fibers showed high CO2 adsorption rates and good selectivities for CO2/N2 and CO2/CH4 separation. After saturation with CO2, the fibers could be easily regenerated and maintained their performance over several adsorption-desorption cycles.

The direct chemical activation of pitch-based stabilized carbon fibers (uncarbonized) with a conventional activating agent (KOH) has been studied for the first time. Unlike the traditional activation method, this shorter route merges the carbonization and activation steps into one simple thermal treatment. It also requires up to a 70% less activating agent for a given porous structure, which can reach values of SBET>1700m2g-1. In addition, the overall yield of the activation process is increased. The advantages obtained open up the way to a novel environmentally friendly industrial method of preparing activated carbon fibers.

A novel type of carbon fibers, obtained by direct chemical activation of stabilized fibers (non-carbonized), is investigated as active electrode material in supercapacitors (SCs). The main advantage of this novel synthetic method is that it avoids the step of carbonization of the stabilized fibers prior to activation, reducing therefore their cost of production. The as-obtained materials exhibit specific capacitances up to 100 F g-1 in aqueous electrolytes (1.0 M H2SO4), values that are not only higher than those obtained with conventional fibers but also comparable to the capacitances of SCs based on well-established reference materials such as commercial activated carbons (ACs). © 2014 Published by Elsevier B.V.

Acute oxygen (O2) sensing is essential for individuals to survive under hypoxic conditions. The carotid body (CB) is the main peripheral chemoreceptor, which contains excitable and O2-sensitive glomus cells with O2-regulated ion channels. Upon exposure to acute hypoxia, inhibition of K+ channels is the signal that triggers cell depolarization, transmitter release and activation of sensory fibers that stimulate the brainstem respiratory center to produce hyperventilation. The molecular mechanisms underlying O2 sensing by glomus cells have, however, remained elusive. Here we discuss recent data demonstrating that ablation of mitochondrial Ndufs2 gene selectively abolishes sensitivity of glomus cells to hypoxia, maintaining responsiveness to hypercapnia or hypoglycemia. These data suggest that reactive oxygen species and NADH generated in mitochondrial complex I during hypoxia are signaling molecules that modulate membrane K+ channels. We propose that the structural substrates for acute O2 sensing in CB glomus cells are “O2-sensing microdomains” formed by mitochondria and neighboring K+ channels in the plasma membrane.

The RADMED project is devoted to the implementation and maintenance of a multidisciplinary monitoring system around the Spanish Mediterranean waters. This observing system is based on periodic multidisciplinary cruises covering the coastal waters, continental shelf and slope waters and some deep stations (>2000 m) from the Westernmost Alboran Sea to Barcelona in the Catalan Sea, including the Balearic Islands. This project was launched in 2007 unifying and extending some previous monitoring projects which had a more reduced geographical coverage. Some of the time series currently available extend from 1992, while the more recent ones were initiated in 2007. The present work updates the available time series up to 2015 (included) and shows the capability of these time series for two main purposes: the calculation of mean values for the properties of main water masses around the Spanish Mediterranean, and the study of the interannual and decadal variability of such properties. The data set provided by the RADMED project has been merged with historical data from the MEDAR/MEDATLAS data base for the calculation of temperature and salinity trends from 1900 to 2015. The analysis of these time series shows that the intermediate and deep layers of the Western Mediterranean have increased their temperature and salinity with an acceleration of the warming and salting trends from 1943. Trends for the heat absorbed by the water column for the 1943–2015 period, range between 0.2 and 0.6 W/m2 depending on the used methodology. The temperature and salinity trends for the same period and for the intermediate layer are 0.002 °C/yr and 0.001 yr−1 respectively. Deep layers warmed and increased their salinity at a rate of 0.004 °C/yr and 0.001 yr−1

This work describes the preparation of isotropic carbon fibres from three anthracene oil-derived pitches of different softening points. The total absence of solid particles (e.g., primary quinoline insoluble (QI) particles) and the high aromatic composition turn these precursors into a promising raw material for the preparation carbon fibres, as they can be used without any pre-treatment. The carbon fibres were prepared by a melting process that involved the spinning of the pitches and subsequent oxidative stabilization with air and carbonisation. Scanning electron microscopy was used to monitor the surface appearance and diameter of the fibres. The results showed that softening point by itself cannot explain the spinning behaviour of the pitches. Therefore, detailed characterisation of the samples by means of size exclusion chromatography, UV-fluorescence spectroscopy, and laser desorption time-of-flight mass spectrometry was used to elucidate the composition of the pitches, especially their molecular weight distributions. The combination of the characterisation of the precursors with the characterisation of the fibres provides an overall vision of the carbon fibre preparation from the pitches and will certainly permit a pre-selection of the most appropriate precursor for this application. © 2010 Elsevier Ltd. All rights reserved.

The suitability of new environmentally-friendly coal-based products for the preparation of cokes with a highly oriented microstructure is investigated. These products (AO-A and AO-B) are obtained from two different stages of the processing of an industrial anthracene oil. The composition and degree of polymerization determine their ability to produce cokes with highly oriented textures. The transformation of AO-A into a highly oriented coke requires pyrolysis temperatures of 450-460°C, residence times of 8-20 h and a pressure of 5 bar, whereas AO-B, which is more polymerized, requires lower temperatures (420-440°C) and shorter residence times (8 h) without the application of any external pressure. The larger extent of highly oriented microstructures present in cokes from AO-A is explained from the greater hydrogen transfer capacity during the coking process. © 2012 Elsevier Ltd. All rights reserved.

A coal-tar-derived mesophase was chemically activated to produce a high surface area (∼3200 m2/g) carbon with a porosity made up of both micropores and mesopores. Its adsorption capacities were found to be among the highest ever reported in literature, reaching values of 860 mg/g and 1200 mg/g for the adsorption of benzene and toluene, respectively, and 1200 mg/g for the combined adsorption of benzene and toluene from an industrial wastewater. Such high values imply that the entire pore system, including the mesopore fraction, is involved in the adsorption process. The almost complete pore filling is thought to be due to the high relative concentrations of the tested solutions, resulting from the low saturation concentration values for benzene and toluene, which were obtained by fitting the adsorption data to the BET equation in liquid phase. The kinetics of adsorption in the batch experiments which were conducted in a syringe-like adsorption chamber was observed to proceed in accordance with the pseudo-second order kinetic model. The combined presence of micropores and mesopores in the material is thought to be the key to the high kinetic performance, which was outstanding in a comparison with other porous materials reported in the literature.

A proper design of heterogeneous molecular catalysts supported on carbon materials requires a systematic study of >metal-carbon support interactions> and their influence on catalytic activity. In this study, hybrid materials containing covalently anchored iridium N-heterocyclic carbene (NHC) organometallic complexes have been successfully prepared from oxidized and partially reduced carbon nanotubes (CNTs). The preparation method for these supported materials relies on the selective functionalization of the superficial hydroxylic groups using the imidazolium salt, 1-(3-hydroxypropyl)-3-methyl-1H-imidazol-3-ium chloride. The hydrogen transfer catalysis activity of these nanotube-based hybrid catalysts was tested by the reduction of cyclohexanone to cyclohexanol with 2-propanol, and the results of the tests were compared with those obtained using similar hybrid graphene-based catalysts. While EXAFS analysis revealed a common first coordination shell of the iridium atom for all the hybrid materials examined, independently of whether they were either supported on carbon nanotubes or graphene materials, catalytic activity in all the reduced materials was significantly superior. Moreover, catalytic systems based on reduced CNTs exhibited a better performance than those based on reduced graphene materials. Both these facts suggest there is a positive correlation between hydrogen transfer catalytic activity, reconstruction of the aromatic carbon structure and the smaller amount of oxygen functional groups.

O2 sensing is essential for mammalian homeostasis. Peripheral chemoreceptors such as the carotid body (CB) contain cells with O2-sensitive K+ channels, which are inhibited by hypoxia to trigger fast adaptive cardiorespiratory reflexes. How variations of O2 tension (PO2) are detected and the mechanisms whereby these changes are conveyed to membrane ion channels have remained elusive. We have studied acute O2 sensing in conditional knockout mice lacking mitochondrial complex I (MCI) genes. We inactivated Ndufs2, which encodes a protein that participates in ubiquinone binding. Ndufs2-null mice lose the hyperventilatory response to hypoxia, although they respond to hypercapnia. Ndufs2-deficient CB cells have normal functions and ATP content but are insensitive to changes in PO2. Our data suggest that chemoreceptor cells have a specialized succinate-dependent metabolism that induces an MCI state during hypoxia, characterized by the production of reactive oxygen species and accumulation of reduced pyridine nucleotides, which signal neighboring K+ channels.

The effect of different N-doping treatments on the CO2 adsorption capacity and kinetics of activated carbons prepared from the same carbonaceous precursor was studied. Non-doped and N-doped activated carbon fibers with similar shape and diameter were considered in this study in order to discard the influence of particle size and morphology. The N-enriched fibers were obtained following different techniques, which led to activated fibers with different content, type and distribution of nitrogen. The porous texture was the main factor determining the CO2 adsorption capacity of the fibers, and treatment with ammonia at high temperature did not exert any positive influence. In contrast, fibers prepared from a pitch/nitrogenized resin blend showed a slightly enhanced CO2 adsorption capacity, which was ascribed to their homogenous distribution of nitrogen in the bulk material occupying internal positions of the carbon matrix. The kinetics of adsorption remarkably increased with the pH of the activated fibers, and the amount of CO2 adsorbed at short time (100s) by the N-enriched fibers was, regardless the methodology used for their N-enrichment, twice higher than that observed for the N-free fibers. These findings prove the suitability of N-enriched activated carbons for use in swing adsorption systems operating at short time cycles.

A multi-step thermal reduction process to produce graphene from graphite oxide was developed to optimize the degree of reduction, its BET surface area and its suitability as electrode in electrochemical energy storage devices. The procedure combines an initial flash pyrolysis to a temperature below 460ºC and a subsequent ramp-heating treatment up to the selected final temperature. With this methodology, the morphology of the graphene materials obtained, which have a great influence in its properties as electrodes, is controlled.

Laser cladding is an effective technique to coat a metallic substrate with a layer of a different nature.It has been widely reported that the most important combined parameters controlling the quality ofthe coating are the specific energy (E) and the powder density ( ). In the present work, clad depositsof Ti6Al4V + 60 wt.% TiC were prepared on a Ti6Al4V substrate using an optimum combination of Ec= 24 J/mm2 and c= 3 mg/mm2. These experiments were performed using a laser power of 400 and600 W, in order to study the effect of laser power on the properties of the clad. The microstructure, phasecomposition and nanohardness of the coatings were investigated by optical microscopy, scanning elec-tron microscopy and X-ray diffraction. During laser processing, TiC can be partially converted to TiCX(X = 0.5) due mainly to the TiC dissolution into the laser-generated melting pool and subsequent precipi-tation during cooling. It was observed that the lower laser power limit reduces primary TiC dissolution butit also promotes secondary carbide alignment at the interface. On the other hand, the damage mechanisminduced by high laser power is dominated by primary TiC particle cracking by the high stress concentra-tion at the particle matrix interface followed by ductile failure of the matrix. It is also remarkable thatirradiance affects the TiC/TiCxratio despite Ecand care fixed and it determines hardness distributioninside the coating.

Enhanced SO2 adsorption of activated carbon fibers is obtained by tailoring a specific micro-mesoporous structure in the fibers. This architecture is obtained via metal catalytic activation of the fibers with a novel precursor, cobalt naphthenate, which contrary to other precursors, also enhances spinnability and carbon fiber yield. In the SO2 oxidation, it is demonstrated that the combination of micropores and large mesopores is the main factor for an enhanced catalytic activity which is superior to that observed in other similar microporous activated carbon fibers. This provides an alternative way for the development of a new generation of catalytic material.

We prepared a series of graphene-like materials by thermal exfoliation/reduction of a graphite oxide (GO) at temperatures between 127 °C and 2400 °C. The extent of the exfoliation and reduction of the GO at different temperatures, as well as the impact on the resultant graphene-like materials (TRGs), were studied through their chemical/structural characterization. The main oxygen loss was observed at 127 °C during the blasting of the GO, which produced its exfoliation into monolayer functionalized TRG with hydroxyl groups and minor amounts of epoxy and carboxyl groups. Above 600 °C, the reduction continued smoothly, with oxygen and hydrogen loss and the conversion of hybridised carbon atoms from sp3 into sp2. 1000 °C appears to be a critical temperature for the efficiency of the reduction process, as the resulting TRG contained <2% oxygen and 81.5% sp2-carbon atoms. The materials obtained at 2000 °C and 2400 °C were almost oxygen-free and the layers exhibited a dramatic restoration of the pristine graphite structure, as confirmed by the increase in the average size of the sp2-domains. The typical disordered stacking of TRGs increases with temperature, although they can be dispersed yielding monolayers at 127 and 300 °C and stacks of up to 4–6 layers above 1000 °C, as determined by AFM.

A series of arylnaphthalimides were designed and synthesized to overcome the dose-limiting cytotoxicity of N-acetylated metabolites arising from amonafide, the prototypical antitumour naphthalimide whose biomedical properties have been related to its ability to intercalate the DNA and poison the enzyme Topoisomerase II. Thus, these arylnaphthalimides were first evaluated for their antiproliferative activity against two tumour cell lines and for their antitopoisomerase II in vitro activities, together with their ability to intercalate the DNA in vitro and also through docking modelization. Then, the well-known DNA damage response in Saccharomyces cerevisiae was employed to critically evaluate whether these novel compounds can damage the DNA in vivo. By performing all these assays we conclude that the 5-arylsubstituted naphthalimides not only keep but also improve amonafide's biological activities.

Two graphene materials, TRGO-1 and TRGO-2, prepared by the thermal exfoliation/reduction at 1000 °C of two graphite oxides with different characteristics, are investigated as positive electrodes in a vanadium redox flow battery (VRFB). A detailed study of their electrochemical response toward the [VO2+]/[VO2+] redox system is carried out through cyclic voltammetry, electrochemical impedance spectroscopy and charge/discharge experiments. As a consequence of the differences in the structure of the parent graphite oxides, TRGO-1 and TRGO-2 exhibit different structural and physicochemical properties resulting in significantly different electrochemical performances toward the vanadium redox reactions. TRGO-1 exhibits a markedly enhanced electrochemical activity (higher peak current densities and lower overpotentials) and a better kinetic reversibility toward the oxidation/reduction vanadium processes than TRGO-2. Furthermore, charge/discharge tests performed on two VRB single cells, the only differing component being the positive electrode, present higher coulombic, voltage and energy efficiency values in that battery containing the TRGO-1 electrode. The better results achieved with this sample are attributed to the higher degree of restoration of the 2D graphitic structure, and to the consequently higher electrical conductivity which increases the heterogeneous electron transfer rate. Moreover, residual hydroxyl groups present may act as active reaction sites and contribute to enhance its electrochemical response.

[EN] In this paper we demonstrate that the yield and size of the graphene oxide sheets (GO) obtained by sonication of graphite oxide (GrO) can be optimized not only by selecting the appropriate exfoliation conditions but also as a function of the crystalline structure of the parent graphite. A larger crystal size in the parent graphite favors GrO exfoliation and yields larger sheets in shorter sonication times, independently of the oxygen content of the GrO. A maximum yield of GO is obtained in all cases, after which no further improvement is achieved and the size of the sheets decreases

[EN] Graphene materials containing different functional groups were prepared from a natural graphite, by means of two different oxidation methods (Hummers and Brodie). It was observed that the differences in the structure of the resultant graphite oxides (GOs) greatly affect the structure of the graphenes resulting from their thermal exfoliation/reduction. Although the oxidation of the graphite was more effective with the modified Hummers method than with Brodie’s method (C/O of 1.8 vs 2.9, as determined by XPS), the former generated a lower residual oxygen content after thermal exfoliation/reduction and a better reconstruction of the 2D graphene structure (with fewer defects). This is explained by the presence of conjugated epoxy and hydroxyl groups in the GO obtained by Brodie’s method, which upon thermal treatment, lead to the incorporation of oxygen into the carbon lattice preventing its complete restoration. Additionally, graphene materials obtained with Brodie’s method exhibit, in general, smaller sheet size and larger surface area.

[EN] We prepared a series of graphene-like materials by thermal exfoliation/reduction of a graphite oxide (GO) at temperatures between 127 °C and 2400 °C. The extent of the exfoliation and reduction of the GO at different temperatures, as well as the impact on the resultant graphene-like materials (TRGs), were studied through their chemical/structural characterization. The main oxygen loss was observed at 127 °C during the blasting of the GO, which produced its exfoliation into monolayer functionalized TRG with hydroxyl groups and minor amounts of epoxy and carboxyl groups. Above 600 °C, the reduction continued smoothly, with oxygen and hydrogen loss and the conversion of hybridised carbon atoms from sp3 into sp2. 1000 °C appears to be a critical temperature for the efficiency of the reduction process, as the resulting TRG contained <2% oxygen and 81.5% sp2-carbon atoms. The materials obtained at 2000 °C and 2400 °C were almost oxygen-free and the layers exhibited a dramatic restoration of the pristine graphite structure, as confirmed by the increase in the average size of the sp2-domains. The typical disordered stacking of TRGs increases with temperature, although they can be dispersed yielding monolayers at 127 and 300 °C and stacks of up to 4–6 layers above 1000 °C, as determined by AFM.

The Western Intermediate Water (WIW) is probably the less studied water mass in the Western Mediterranean (WMED). It is clearly identifiable as a temperature minimum above the Levantine Intermediate Water (LIW). The WIW circulation from the northern part of the WMED to the south and through the Balearic Channels is well known, but no specific experiments have been devoted to the study of the formation process of this water mass. It is usually accepted, in a vague sense, that WIW is formed in the northern sector of the WMED, in areas surrounding the Gulf of Lions, the Ligurian Sea and the Catalan Sea, being advected towards the Balearic Channels as part of the northern current. The present work shows hydrographic data obtained in late winter in 2010 after severe storms in the WMED. These data show intermediate convective mixing along the whole continental shelf of the Iberian Peninsula, as far to the south as Cape Palos. The data analysed show that, under severe winter conditions, the formation area of WIW is larger than previously thought and the salinity and temperature ranges for this water mass are also wider than those traditionally accepted in the literature. © 2012 Elsevier B.V.

[EN] The effect of the parent graphite on the structure of graphene oxide (GO) is investigated using high purity graphites with a uniform crystallite size. Our results provide direct evidence of how the size of the graphite crystal affects the oxidation process and the functionality and sheet size of the resulting GO. The important role of the crystal boundaries in the graphite with smaller crystallites is confirmed by the smaller size of the GO sheets obtained and also by the presence of carboxylic groups, located at the edges of the sheets. However, functionalization in the graphite with larger crystals mainly occurs in the vicinity of basal plane defects, as evidenced by the larger number of epoxy groups. Thus, this study leads to a better understanding of the oxidation process of graphite and provides a way to produce GOs suitable for different applications.

Crude oil incompatibility is a common problem in the oil industry and may lead to severe fouling of process units, such as the pre-distillation heat exchanger train. This work investigates the use of ellipsometry to evaluate the compatibility of crude oil blends. Two crude oils with predicted regions of compatibility and incompatibility were blended in several ratios and the formation of a denser phase was examined by ellipsometry. The procedure implies the evaluation of the real part of the refractive index of the crude oils and their mixtures, which can be linked to the density of the mixture. The ellipsometric measurements fit well theoretical predictions obtained using a Cauchy dielectric function for the pure crudes and the Maxwell-Garnett effective medium model for the mixtures. The regions of compatibility and incompatibility between the two crudes were checked against independent measurements of deposit formation by weight and predictions based on the insolubility and solubility blending numbers, showing good agreement. © 2011 Elsevier B.V.

The deep waters in the Western Mediterranean (>600m) are the result of mixing between the two water masses above it (Atlantic Water, 0-200. m and Levantine Intermediate Water, 200-600. m) and heat and buoyancy losses in late winter. Deep waters in the Western Mediterranean have undergone a continuous warming during the second half of the twentieth century and initially it was hypothesized that this had been caused by the warming of the contributing water masses, very likely linked to global warming. Nevertheless, no clear signals of warming have been detected in the intermediate layers and no warming trends were detected in the upper layer before the 1980s. This fact suggested that the cause of deep water warming could be linked to river damming and the consequent salinity increase, instead of to an increase of the heat absorbed by the upper ocean, as in other parts of the world ocean. In this work we use the data base MEDATLAS and data from more recent monitoring programs to construct the longest temperature and salinity time series ever analysed in the Western Mediterranean (1900 to 2008). These time series show that both the upper and intermediate layers have warmed throughout the twentieth century. Long term and decadal variability in the upper layer correlate with surface air temperature in the northern hemisphere and heat absorbed by the upper North Atlantic Ocean, suggesting that the time series analysed in this work reflect the present heat absorption of the oceans in the context of global warming. The present data set highlights the importance of monitoring programs and provides a proxy for the study of climate change

This study describes the application of a multilocus sequence typing (MLST) analysis for molecular discrimination at the strain level of Spanish wine yeast strains. The discrimination power of MLST is compared to mitochondrial RFLP analysis. Fragments of the ADP1, ACC1, RPN2, GLN4, and ALA1 genes were amplified by PCR from chromosomal DNA of 18 wine Saccharomyces cerevisiae strains. Ten polymorphic sites were found in the five loci analyzed showing 13 different genotypes, with 11 of them represented by only one strain. RFLP analysis of the same 18 wine yeast strains showed seventeen different mitochondrial patterns. Phylogenetic relationships among the strains analyzed, inferred by MLST data, showed wine isolates of S. cerevisiae as a rather homogeneous group. The discrimination potential of mitochondrial RFLP analysis was superior to the MLST scheme used in this work. However, MLST analysis allowed an easy construction of reliable phylogenetic trees. MLST analysis offers the possibility of typing wine S. cerevisiae strains simultaneously to the study of the genetic relationship among them

This study deals with the adsorption of Cr(VI) from synthetic and industrial wastewater, produced by a sewage plant. The activated carbons were prepared from a lignocellulosic raw material by thermal treatment at 450 and 650°C in the presence of acid (AlCl3, HCl, H3PO4 and H2SO4) and base (NaOH) agents. To optimize the adsorption of Cr(VI), the chemical modifications caused by each activating agent (related to the capability of Cr(VI) removal), and the optimal experimental conditions of the pH, Cr(VI) concentration, adsorbent dose and residence time, were studied. Thus, treatment with H3PO4 gives rise to carbons with a high surface area and high efficiency for Cr(VI) removal at short equilibrium times. In contrast, the generation of active surface sites by means of NaOH requires longer equilibrium times, the adsorption being less effective than in the former case. The adsorption isotherms obey the Langmuir equation only in the first stages of the reaction but fit the Freundlich equations over the whole range studied, so the heat of adsorption can be easily calculated. The results also show that the activated carbons obtained can be recovered by filtration with an efficiency of 30% in the third cycle.

[EN]MKARE®, a 100% natural ingredient derived from fresh eggshell membrane (ESM), has a rich composition in bioactive compounds like collagen, hyaluronic acid, and elastin. These components are beneficial for managing osteoarthritis (OA) due to their anti-inflammatory and regenerative properties. Highlighting the significance of freshness, our research has shown that the effectiveness of MKARE® is higher than that of other commercial products based on ESM that have been stored for several days at room temperature, losing their bioactive compounds. This study explores the MKARE® anti-inflammatory capacity through an in vitro and clinical analyses, demonstrating its ability to alleviate OA symptoms and improve joint health. This underscores the crucial role of freshness in optimizing the therapeutic benefits.