2,361 research outputs found

    Biotransformation of indigo carmine to isatin sulfonic acid by lyophilized mycelia from Trametes versicolor

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    Indigo carmine (IC) was biotrasformed to 5-isatinsulfonic acid using intracellular and associated enzymes from Trametes versicolor lyophilized mycelia; even when extracellular enzymes were absent, in high concentration solutions of IC (4 000 mg L-1) and non-sterile condition. T. versicolor was grown in wheat strew and malt extract liquid medium and harvested during the stationary growth phase, it was lyophilized and made to react with indigo carmine. Experimental series were performed at different IC concentrations (from 100 to 4000 mg L-1). Color removal was 99.90, 98.75, 88.35, 79.47, 70.0 and 40.35% for 100, 500, 1000, 2000, 3000 and 4000 mg L-1 of IC, respectively after 120 h with exception for 100 mg L-1 of IC, which reached total color removal after 1 h. Reacted mixture byproducts were separated by column chromatography. IC biotransformation to 5-isatinsulfonic acid was confirmed by HPLC, UV-VIS, FT- IR, 1H and 13C NMR spectroscopy. Activity of laccase from lyophilized mycelia was conserved after one year at 4°C. Dehydrated biological material in colorant biodegradation is a new method which allows obtaining high discoloration efficiencies. Lyophilized mycelia could be more stable than traditionally used wet biomass or liquid culture for biodegradation of color dye.Key words: Biodegradation, indigo carmine, Trametes versicolor

    Plasmodium diversity in non-malaria individuals from the Bioko Island in Equatorial Guinea (West Central-Africa)

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    BACKGROUND: In this paper we analyse the Plasmodium sp. prevalence in three villages with different isolation status on the island of Bioko (Equatorial Guinea) where malaria is a hyper-endemic disease. We also describe the genetic diversity of P. falciparum, using several plasmodia proteins as markers which show a high degree of polymorphism (MSP-1 and MSP-2). The results obtained from three different populations are compared in order to establish the impact of human movements and interventions. METHODS: Plasmodium sp. were analysed in three villages on Bioko Island (Equatorial Guinea), one of which (Southern) is isolated by geographical barriers. The semi-nested multiplex polymerase chain reaction (PCR) technique was used to determine the prevalence of the four human plasmodia species. The genotyping and frequency of P. falciparum populations were determined by PCR assay target polymorphism regions of the merozoite surface proteins 1 and 2 genes (MSP-1 and MSP-2). RESULTS: The data obtained show that there are no differences in plasmodia population flow between the Northwest and Eastern regions as regards the prevalence of the different Plasmodium species. The Southern population, on the other hand, shows a minor presence of P. malariae and a higher prevalence of P. ovale, suggesting some kind of transmission isolated from the other two. The P. falciparum genotyping in the different regions points to a considerable allelic diversity in the parasite population on Bioko Island, although this is somewhat higher in the Southern region than the others. There was a correlation between parasitaemia levels and the age of the individual with the multiplicity of infection (MOI). CONCLUSION: Results could be explained by the selection of particular MSP alleles. This would tend to limit diversity in the parasite population and leading up to the extinction of rare alleles. On the other hand, the parasite population in the isolated village has less outside influence and the diversity of P. falciparum is maintained higher. The knowledge of parasite populations and their relationships is necessary to study their implications for control intervention

    Eye-to-hand calibration of an industrial robotic arm with structured light 3D cameras

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    [EN] Computer vision is gaining more and more importance in the world of industrial robotics, since it is necessary to carry out increasingly precise and autonomous tasks, which is why a more exact positioning of the robot is needed. This requires the support of a vision system that is the one that gives the robot precision in its pose, calibrating said system with respect to the robot. This work presents a simple methodology to approach this form of calibration, called hand-eye, using a structured light 3D camera that obtains information from the real world and a six-axis industrial robotic arm. The method uses the RANSAC algorithm for the determination of the planes, which represents a notable reduction in errors, since the coordinates of the points sought come from planes adjusted to thousands of points. This allows the system to always have the ability to obtain a transformation matrix from the coordinates of the camera to the base of the robot. In addition, the proposed method is ideal for making a precision comparison between cameras, due to its simplicity and speed of use. In this study, the resulting error analysis was performed using two dfferent 3D cameras: a basic one (Kinect 360) and an industrial one (Zivid ONE + M).[ES] La visión artificial está cobrando cada día más auge en el mundo de la robótica industrial, ya que es necesario realizar tareas cada vez más precisas y autónomas, por lo que se necesita un posicionamiento del robot más exacto. Para ello se precisa del apoyo de un sistema de visión que sea el que preste al robot precisión en su pose, calibrando dicho sistema con respecto al robot. Este trabajo presenta una metodología sencilla para abordar esta forma de calibración, llamada ojo a mano, empleando una cámara 3D de luz estructurada que obtiene la información del mundo real y un brazo robótico industrial de seis ejes. Esto permite utilizar el algoritmo RANSAC para la determinación de los planos, cuya intersección nos da las coordenadas de los puntos,lo que supone una reducción notable de los errores, ya que las coordenadas proceden de planos ajustados a miles de puntos, lo cual hace que el sistema sea más robusto y capaz de obtener una matriz de transformación de las coordenadas de la cámara a la base del robot, que le permitirá abordar cualquier tarea que precise con una precisión eficiente. Se ha realizado el análisis de errores resultante utilizando dos cámaras 3D diferentes: una básica (Kinect 360) y otra industrial (Zivid ONE+ M).Este trabajo ha sido realizado parcialmente gracias al apoyo del Plan Estatal de Investigación Científica y Técnica y de Innovación 2017-2020 (AUROVI) EQC2018-005190-P. Fernando M. Quintana agradece al Ministerio de Ciencia, Innovación y Universidades de España su apoyo a través de la ayuda FPU (FPU18/04321).Diaz-Cano, I.; Quintana, FM.; Galindo, PL.; Morgado-Estevez, A. (2022). Calibración ojo a mano de un brazo robótico industrial con cámaras 3D de luz estructurada. Revista Iberoamericana de Automática e Informática industrial. 19(2):154-163. https://doi.org/10.4995/riai.2021.16054OJS15416319

    Susceptibility patterns and molecular identification of Trichosporon species

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    The physiological patterns, the sequence polymorphisms of the internal transcriber spacer (ITS), and intergenic spacer regions (IGS) of the rRNA genes and the antifungal susceptibility profile were evaluated for their ability to identify Trichosporon spp. and their specificity for the identification of 49 clinical isolates of Trichosporon spp. Morphological and biochemical methodologies were unable to differentiate among the Trichosporon species. ITS sequencing was also unable to differentiate several species. However, IGS1 sequencing unambiguously identified all Trichosporon isolates. Following the results of DNA-based identification, Trichosporon asahii was the species most frequently isolated from deep sites (15 of 25 strains; 60%). In the main, other Trichosporon species were recovered from cutaneous samples. The majority of T. asahii, T. faecale, and T. coremiiforme clinical isolates exhibited resistance in vitro to amphotericin B, with geometric mean (GM) MICs >4 mug/ml. The other species of Trichosporon did not show high MICs of amphotericin B, and GM MICs were <1 mug/ml. Azole agents were active in vitro against the majority of clinical strains. The most potent compound in vitro was voriconazole, with a GM MIC </=0.14 mug/ml. The sequencing of IGS correctly identified Trichosporon isolates; however, this technique is not available in many clinical laboratories, and strains should be dispatched to reference centers where these complex methods are available. Therefore, it seems to be more practical to perform antifungal susceptibility testing of all isolates belonging to Trichosporon spp., since correct identification could take several weeks, delaying the indication of an antifungal agent which exhibits activity against the infectious strain.S

    Metallofluorescent Nanoparticles for Multimodal Applications

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    Herein, we describe the synthesis and application of cross-linked polystyrene-based dual-function nano- and microparticles containing both fluorescent tags and metals. Despite containing a single dye, these particles exhibit a characteristic dual-band fluorescence emission. Moreover, these particles can be combined with different metal ions to obtain hybrid metallofluorescent particles. We demonstrate that these particles are easily nanofected into living cells, allowing them to be used for effective fingerprinting in multimodal fluorescence-based and mass spectrometry-based flow cytometry experiments. Likewise, the in situ reductions of the metal ions enable other potential uses of the particles as heterogeneous catalysts

    The M_BH - M_star relation for X-ray obscured, red QSOs at 1.2< z <2.6

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    We present near-infrared spectra, obtained with SINFONI and XShooter observations at ESO VLT, of nine dusty, red QSOs at 1.2<z<2.6. The sources are hard X-ray detected, characterized by cold absorption (N_H>10^{21} - 10^{22} cm^{-2}) and show a broad Ha component in the NIR spectra. We complement this sample with twelve additional sources taken from the literature with similar properties resulting in a total sample of 21 X-ray obscured, intermediate type (1.8-1.9), dusty reddened QSOs. From the broad Ha line we have computed the BH masses through the virial formula and derived Eddington ratios. Moreover, from optical/IR multi-component SED fitting we have derived the stellar mass of their host galaxies and their SFRs. We find that most of the sources in our sample are hosted in starburst and main sequence star-forming galaxies with Eddington ratios lambda>0.1. We find a strong trend with the BH mass i.e. less massive objects are scattered below and above the local relation while the most massive ones are mainly located above it. We also studied the evolution of these sources on the M_BH-M_star plane compared to a sample of optically blue type--1 QSOs and we find that obscured red QSOs show a ratio of M_BH to M_star that increases with redshift which is consistent with or slightly lower than what has been found for blue QSOs. These sources may represent the blow-out phase at the end of the rapid BH growth and immediately preceding the classical blue QSOs typically sampled in optical surveys. They in fact show evidence of outflows in the ionized gas component, but their BH has already fully formed.Comment: 17 pages, 7 figures accepted for publication in MNRAS in MNRA

    The rest-frame ultraviolet properties of radio-loud broad absorption line quasars

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    We recently presented radio observations of a large sample of radio-loud broad absorption line (BAL) quasars from the SDSS and FIRST surveys, as well as a well matched sample of unabsorbed quasars, primarily to measure their radio spectral indices and estimate ensemble orientations. Here, we analyze the SDSS spectra of these samples and compare the rest-frame ultraviolet properties of radio-loud BAL and non-BAL quasars. Ultraviolet properties include the continuum shape, emission-line measurements of C IV, Al III, C III], Fe II, and Mg II, and BAL properties including the balnicity index (BI), absorption index (AI), and minimum and maximum outflow velocities. We find that radio-loud BAL quasars have similar ultraviolet properties compared to radio-loud non-BAL sources, though they do appear to have redder continua and stronger Fe II emission, which is consistent with what is found for radio-quiet BAL sources. No correlations exist between outflow properties and orientation (radio spectral index), suggesting that BAL winds along any line of sight are driven by the same mechanisms. There are also few correlations between spectral index and other properties. We conclude that BAL outflows occur along all lines of sight with similar strengths and velocities.Comment: Accepted for publication in MNRAS. Tables 1 and 2 will be published in full with the final online publicatio

    SSDSS IV MaNGA - Properties of AGN host galaxies

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    We present here the characterization of the main properties of a sample of 98 AGN host galaxies, both type-II and type-I, in comparison with those of about 2700 non-active galaxies observed by the MaNGA survey. We found that AGN hosts are morphologically early-type or early-spirals. For a given morphology AGN hosts are, in average, more massive, more compact, more central peaked and rather pressurethan rotational-supported systems. We confirm previous results indicating that AGN hosts are located in the intermediate/transition region between star-forming and non-star-forming galaxies (i.e., the so-called green valley), both in the ColorMagnitude and the star formation main sequence diagrams. Taking into account their relative distribution in terms of the stellar metallicity and oxygen gas abundance and a rough estimation of their molecular gas content, we consider that these galaxies are in the process of halting/quenching the star formation, in an actual transition between both groups. The analysis of the radial distributions of the starformation rate, specific star-formation rate, and molecular gas density shows that the quenching happens from inside-out involving both a decrease of the efficiency of the star formation and a deficit of molecular gas. All the intermediate data-products used to derive the results of our analysis are distributed in a database including the spatial distribution and average properties of the stellar populations and ionized gas, published as a Sloan Digital Sky Survey Value Added Catalog being part of the 14th Data Release: http://www.sdss.org/dr14/manga/manga-data/manga-pipe3d-value-added-catalog/Comment: 48 pages, 14 figures, in press in RMxA
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