Kinematic study of planetary nebulae in NGC 6822

By measuring precise radial velocities of planetary nebulae (which belong to the intermediate age population), H II regions, and A-type supergiant stars (which are members of the young population) in NGC 6822, we aim to determine if both types of population share the kinematics of the disk of H I found in this galaxy. Spectroscopic data for four planetary nebulae were obtained with the high spectral resolution spectrograph Magellan Inamori Kyocera Echelle (MIKE) on the Magellan telescope at Las Campanas Observatory. Data for other three PNe and one H II region were obtained from the SPM Catalog of Extragalactic Planetary Nebulae which employed the Manchester Echelle Spectrometer attached to the 2.1m telescope at the Observatorio Astron\'omico Nacional, M\'exico. In the wavelength calibrated spectra, the heliocentric radial velocities were measured with a precision better than 5-6 km s$^{-1}$. Data for three additional H II regions and a couple of A-type supergiant stars were collected from the literature. The heliocentric radial velocities of the different objects were compared to the velocities of the H i disk at the same position. From the analysis of radial velocities it is found that H II regions and A-type supergiants do share the kinematics of the H I disk at the same position, as expected for these young objects. On the contrary, planetary nebula velocities differ significantly from that of the H I at the same position. The kinematics of planetary nebulae is independent from the young population kinematics and it is closer to the behavior shown by carbon stars, which are intermediate-age members of the stellar spheroid existing in this galaxy. Our results are confirming that there are at least two very different kinematical systems in NGC 6822

A systematic literature review on the development and use of mobile learning (web) apps by early adopters

Surveys in mobile learning developed so far have analysed in a global way the effects on the usage of mobile devices by means of general apps or apps already developed. However, more and more teachers are developing their own apps to address issues not covered by existing m-learning apps. In this article, by means of a systematic literature review that covers 62 publications placed in the hype of teacher-created m-learning apps (between 2012 and 2017, the early adopters) and the usage of 71 apps, we have analysed the use of specific m-learning apps. Our results show that apps have been used both out of the classroom to develop autonomous learning or field trips, and in the classroom, mainly, for collaborative activities. The experiences analysed only develop low level outcomes and the results obtained are positive improving learning, learning performance, and attitude. As a conclusion of this study is that the results obtained with specific developed apps are quite similar to previous general surveys and that the development of long-term experiences are required to determine the real effect of instructional designs based on mobile devices. These designs should also be oriented to evaluate high level skills and take advantage of mobile features of mobile devices to develop learning activities that be made anytime at anyplace and taking into account context and realistic situations. Furthermore, it is considered relevant the study of the role of educational mobile development frameworks in facilitating teachers the development of m-learning apps

Experimental recreation of the evolution of lignin-degrading enzymes from the Jurassic to date

[Background] Floudas et al. (Science 336: 1715) established that lignin-degrading fungi appeared at the end of Carboniferous period associated with the production of the first ligninolytic peroxidases. Here, the subsequent evolution of these enzymes in Polyporales, where most wood-rotting fungi are included, is experimentally recreated using genomic information.[Results] With this purpose, we analyzed the evolutionary pathway leading to the most efficient lignin-degrading peroxidases characterizing Polyporales species. After sequence reconstruction from 113 genes of ten sequenced genomes, the main enzyme intermediates were resurrected and characterized. Biochemical changes were analyzed together with predicted sequences and structures, to understand how these enzymes acquired the ability to degrade lignin and how this ability changed with time. The most probable first peroxidase in Polyporales would be a manganese peroxidase (Mn3+ oxidizing phenolic lignin) that did not change substantially until the appearance of an exposed tryptophan (oxidizing nonphenolic lignin) originating an ancestral versatile peroxidase. Later, a quick evolution, with loss of the Mn2+-binding site, generated the first lignin peroxidase that evolved to the extant form by improving the catalytic efficiency. Increased stability at acidic pH, which strongly increases the oxidizing power of these enzymes, was observed paralleling the appearance of the exposed catalytic tryptophan.[Conclusions] We show how the change in peroxidase catalytic activities meant an evolutionary exploration for more efficient ways of lignin degradation by fungi, a key step for carbon recycling in land ecosystems. The study provides ancestral enzymes with a potential biotechnological interest for the sustainable production of fuels and chemicals in a biomass-based economy.We acknowledge support of the publication fee by the CSIC Open Access Publication Support Initiative through its Unit of Information Resources for Research (URICI), and the EC OpenAIRE FP7 post-grant Open Access Pilot.This work was supported by the INDOX (KBBE-2013-613549) and EnzOx2 (H2020-BBI-PPP-2015-2-720297) EU projects and the NOESIS (BIO2014-56388-R) project of the Spanish Ministry of Economy and Competitiveness (MINECO). The work conducted by JGI was supported by the Office of Science of the U.S. Department of Energy under Contract DE-AC02-05CH11231.EUR 1,620 APC fee funded by the EC FP7 Post-Grant Open Access Pilo

Umbrales económicos para la araña roja Tetranychus urticae (acari: Tetranychidae) en mandarino

Tetranychus urticae es una plaga clave en cítricos, especialmente en mandarina clementina. Se evaluó el daño de este ácaro sobre la producción de 24 árboles de clementino durante tres años consecutivos. Los árboles fueron visitados semanalmente, y se estimó tanto la población de araña roja como la de ácaros fitoseidos, así como la brotación. Al final de cada temporada, se recolectaron las clementinas, se pesaron, y se evaluó el daño ocasionado por T. urticae en fruto. Se encontró una relación negativa entre la densidad de la araña roja y el rendimiento (kg/árbol). Sin embargo, las correlaciones entre el daño en fruto y los diferentes estimadores de araña roja fueron más fuertes. Las regresiones multivariantes destacaron el papel clave que juegan tanto los ácaros fitoseidos como la brotación, que se correlacionaron negativamente con el daño en fruto. El período más corto de muestreo que predijo satisfactoriamente el daño en fruto en la recolección, se extendió desde el 1 agosto hasta mediados de octubre. A efectos de Gestión Integrada de Plagas, se estimó un umbral económico de daños de 31,14 hembras adultas de araña roja en hoja sintomática por m2. Teniendo en cuenta la dinámica poblacional de T. urticae, el umbral de intervención varió de 10 a 15 hembras adultas de araña roja en hoja sintomática por m2 . Cuando se supera este umbral, los agricultores tendrían una ventana de una semana para aplicar cualquiera de las medidas (biológicas o químicas) que disponen contra T. urticae.Este trabajo fue parcialmente finan- ciado por el Ministerio de Ciencia e Innovación (proyectos AGL2011- 30538-C03-01-07464 AGL2004-C03- 01, AGL2005-07155-C03, y AGL2008- 05287-C04-03/AGR). S.P.R. y E.A.F. fueron beneficiarias de una beca pre- doctoral del MICINN y de la UJI, respectivamente

Enhanced degradation of softwood versus hardwood by the white-rot fungus Pycnoporus coccineus

16 p.-8 fig.-1 tab. Courier, Marie et al.This study was also funded by the French National Research Agency (A*MIDEX project ANR11-IDEX-0001-02;ANR FUNLOCK ANR-13-BIME-0002-01). The work by the US Department of Energy Joint Genome Institute, a DOE Office of Science User Facility, is supported by the Office of Science of the US Department of Energy under Contract No. DE-AC02-05CH11231.Peer reviewe

Ac magnetic susceptibility of a molecular magnet submonolayer directly patterned onto a microSQUID sensor

We report the controlled integration, via Dip Pen Nanolithography, of monolayer dots of ferritin-based CoO nanoparticles (12 Bohr magnetons) into the most sensitive areas of a microSQUID sensor. The nearly optimum flux coupling between these nanomagnets and the microSQUID improves the achievable sensitivity by a factor 100, enabling us to measure the linear susceptibility of the molecular array down to very low temperatures (13 mK). This method opens the possibility of applying ac susceptibility experiments to characterize two-dimensional arrays of single molecule magnets within a wide range of temperatures and frequencies.Comment: 4 pages 3 figure

Aplicaciones analíticas de la reducción fotoquímica de la riboflavina el ácido etilenodiaminotetraacético. Determinación de ioduro

A kinetic study of the photochemical reaction of riboflavin and EDTA (in the absence of oxygen) has been made in connection with development of a new kinetic method for iodide. The reaction is first-order with respect to riboflavin, EDTA and absorbed light-intensity. The rate of photoreduction is strongly pH^dependent, and maximal at about pH 7,5. The photoreduction involves a long-Uved excited state of the vitamin B2 and is dramaticalUy retarded by small amounts of iodide. A tenta'tive mechanism is proposed, and the experimental conditions have been optimized. The variable time method appears to be the most suitable for determination of iodide. A detection limit of 8 [xg/rnl and a casfficient of variation about 3 % can be adhieved. Chloride and bromide do not interfere at levéis below 100-fold mole ratio to iodide. Metal ions do not interfere if enough excess of EDTA is used.Se ha estudiado la reacción fotoquímica entre la riboflavina y el ácido etilenodiaminotetraacético (en ausencia de oxígeno) con la finalidad de desarrollar un método cinético para la determinación de ioduro. La reacción es de primer orden con respecto a la riboflavina, AEDT e intensidad de la radiación absorbida. La velocidad del proceso fotoquímico depende del pH y es máxima a pH 7,2. La fotorreducción tiene lugar a través de estados excitados de larga vida de la vitamina B2 y está muy afectada por la presencia de pequeñas cantidades de ioduro. Se propone un posible mecanismo y se han estudiado todas las variables con la finalidad de optimizar las condiciones del método analítico. Se ha empleado el procedimiento del tiempo variable como el más apropiado para la determinación de ioduro. La sensibilidad es de 8 fig/ml y el coeficien'te de variación del 3 %. Los iones bromuro y cloruro son compatibles hasta la relación 100/1. La interferencia de los iones metálicos se elimina añadiendo un exceso de AEDT

Stability of the factorial structure of metabolic syndrome from childhood to adolescence: a 6-year follow-up study

Background Metabolic syndrome (MS) is a clustering of cardiometabolic risk factors that is considered a predictor of cardiovascular disease, type 2 diabetes and mortality. There is no consistent evidence on whether the MS construct works in the same way in different populations and at different stages in life. Methods We used confirmatory factor analysis to examine if a single-factor-model including waist circumference, triglycerides/HDL-c, insulin and mean arterial pressure underlies metabolic syndrome from the childhood to adolescence in a 6-years follow-up study in 174 Swedish and 460 Estonian children aged 9 years at baseline. Indeed, we analyze the tracking of a previously validated MS index over this 6-years period. Results The estimates of goodness-of-fit for the single-factor-model underlying MS were acceptable both in children and adolescents. The construct stability of a new model including the differences from baseline to the end of the follow-up in the components of the proposed model displayed good fit indexes for the change, supporting the hypothesis of a single factor underlying MS component trends. Conclusions A single-factor-model underlying MS is stable across the puberty in both Estonian and Swedish young people. The MS index tracks acceptably from childhood to adolescence.This study was supported by grants from the Estonian Ministry of Education and Science (No 0180027 and 0942706) and the Estonian Science Foundation (No 6932 and 6788). The study was also supported by grants from the Stockholm County Council, the Spanish Ministry of Education (EX-2008-0641), the Spanish Ministry of Science and Innovation (RYC-2010-05957), and the Swedish Council for Working Life and Social Research, the Swedish Heart-Lung Foundation (20090635)

Clinical impact of the methodological quality of fetal doppler standards in the management of fetal growth restriction

Esta tesis, que lleva por título “Clinical impact of the methodological quality of fetal Doppler standards in the management of fetal growth Restriction”, es un trabajo realizado en la Universidad de Zaragoza con colaboración de la Universidad de Oxford por lo que opta a la mención internacional. Además, está elaborada según la normativa de la Universidad de Zaragoza como tesis por compendio de publicaciones, con 4 artículos publicados en revistas de elevado factor de impacto.El crecimiento intrauterino restringido (CIR) es una de las enfermedades con mayor repercusión médica, social y económica en obstetricia. Estos fetos pueden interrumpir su crecimiento como consecuencia de una insuficiencia placentaria, apareciendo alteraciones en el Doppler fetal, lo que conlleva un riesgo elevado de resultado perinatal adverso. Para que una herramienta como el Doppler fetal sea fiable, los valores obtenidos deben ser adecuados y reproducibles, la medición del Doppler debe estar estandarizada y así, maximizaremos su potencial en la evaluación del CIR en la práctica clínica. Con este objetivo se desarrolló la primera de las publicaciones que propone un sistema de puntuación objetiva para evaluar imágenes Doppler de la arteria cerebral media (ACM), demostrando que los controles de calidad de imágenes son esenciales, así como el uso de sistemas objetivos que hagan que las imágenes sean reproducibles.Por otro lado, la secuencia de progresión del Doppler fetal ha sido descrita claramente y hay evidencia de que los cambios cualitativos en el Doppler de la arterial umbilical (AU), como la presencia, ausencia o inversión del flujo diastólico, indican un mayor riesgo de muerte fetal. Sin embargo, la asociación entre los cambios semi-cuantitativos en el Doppler de AU y ACM (medidos con el índice de pulsatilidad) y los resultados perinatales y a largo plazo no se han establecido claramente. Como consecuencia, se han publicado multitud de valores de referencia del índice de pulsatilidad del Doppler fetal. Esta falta de evidencia podría explicarse, al menos parcialmente, por la calidad metodología utilizada para establecer estos valores, lo que podría tener importantes implicaciones para la práctica clínica. Con esta hipótesis, en el segundo trabajo se realizó una revisión sistemática de todos los estudios publicados con el objetivo de crear curvas de referencia para la AU, ACM e índice cerebroplacentario (ICP). Tras utilizar una lista de verificación ya validada y evaluar 38 estudios, se llegó a la conclusión de que todos los estudios en los que se basan los valores de referencia que se usan en la práctica clínica tienen numerosos sesgos metodológicos, haciendo que las diferencias entre los valores sean importantes. Además, en el tercer estudio, se comparó todos estos valores demostrando su gran variabilidad y se realizó una simulación clínica en la que se observó que el manejo de un feto con crecimiento intrauterino restringido puede variar en dependencia del valor de referencia que se elija, decidiendo finalizar la gestación o no y produciendo en algunos casos prematuridad iatrogénica y en otros, aumento del riesgo de muerte fetal intrauterina.Finalmente, como solución a todos los problemas planteados y a la falta de estudios de alta calidad metodológica en los que basar nuestras actuaciones médicas, se propone el estudio FETHUS, un estudio de cohortes, longitudinal, multicéntrico, internacional y prospectivo, con el objetivo de crear unos valores de referencia basados en un estudio con alta calidad metodológica que sirvan de referencia universal para el Doppler fetal, unificando así el manejo del feto con crecimiento intrauterino restringido.1. Alfirevic Z, Stampalija T, Dowswell T. Fetal and umbilical Doppler ultrasound in high-risk pregnancies. Vol. 2017, Cochrane Database of Systematic Reviews. John Wiley and Sons Ltd; 2017. 2. Alfirevic Z, Stampalija T, Medley N. Fetal and umbilical Doppler ultrasound in normal pregnancy. Vol. 2015, Cochrane Database of Systematic Reviews. John Wiley and Sons Ltd; 2015. 3. Fetal Growth Restriction. Practice Bulletin No. 134. American College of Obstetricians & Gyncologists. Obstet Gynecol. 2013;4. Gordijn SJ, Beune IM, Thilaganathan B, Papageorghiou A, Baschat AA, Baker PN, et al. Consensus definition of fetal growth restriction: a Delphi procedure. Ultrasound Obstet Gynecol [Internet]. 2016 Sep [cited 2019 Aug 3];48(3):333–9. Available from: http://www.ncbi.nlm.nih.gov/pubmed/269096645. RCOG Green-top Guideline, 2nd Edition J 2014. Investigation and Management of the Small for Gestational Age Fetus. R Coll Obstet Gynaecol (RCOG) [Internet]. Available from: http://www.rcog.org.uk/files/rcog-corp/6. Conde-Agudelo A, Villar J, Kennedy SH, Papageorghiou AT. Predictive accuracy of cerebroplacental ratio for adverse perinatal and neurodevelopmental outcomes in suspected fetal growth restriction: systematic review and meta-analysis. Ultrasound Obstet Gynecol. 2018; 7. Oros D, Figueras F, Cruz-Martinez R, Padilla N, Meler E, Hernandez-Andrade E, et al. Middle versus anterior cerebral artery Doppler for the prediction of perinatal outcome and neonatal neurobehavior in term small-for-gestational-age fetuses with normal umbilical artery Doppler. Ultrasound Obstet Gynecol [Internet]. 2010 Apr [cited 2019 Aug 22];35(4):456–61. Available from: http://www.ncbi.nlm.nih.gov/pubmed/201781158. DeVore GR. The importance of the cerebroplacental ratio in the evaluation of fetal well-being in SGA and AGA fetuses. Vol. 213, American Journal of Obstetrics and Gynecology. Mosby Inc.; 2015. p. 5–15. 9. Arduini D, Rizzo G. Normal values of Pulsatility Index from fetal vessels: a cross-sectional study on 1556 healthy fetuses. J Perinat Med [Internet]. 1990 [cited 2019 Aug 3];18(3):165–72. Available from: http://www.ncbi.nlm.nih.gov/pubmed/220086210. Morales-Roselló J, Diaz García-Donato J. Study of fetal femoral and umbilical artery blood flow by Doppler ultrasound throughout pregnancy.11. Figueras F, Gardosi J. Intrauterine growth restriction: New concepts in antenatal surveillance, diagnosis, and management. Vol. 204, American Journal of Obstetrics and Gynecology. Mosby Inc.; 2011. p. 288–300.12. Royston P, Wright EM. How to construct “normal ranges” for fetal variables. Ultrasound Obstet Gynecol. 1998;11(1):30–8.13. Ruiz-Martinez S, Volpe G, Vannuccini S, Cavallaro A, Impey L, Ioannou C. An objective scoring method to evaluate image quality of middle cerebral artery Doppler. J Matern Fetal Neonatal Med [Internet]. 2018 Jun 27 [cited 2019 Sep 12];1–181. Available from: http://www.ncbi.nlm.nih.gov/pubmed/2995015614. Salomon LJ, Bernard JP, Duyme M, Buvat I, Ville Y. The impact of choice of reference charts and equations on the assessment of fetal biometry. Ultrasound Obstet Gynecol. 2005 Jun;25(6):559–65.<br /

Biodegradation of lignocellulosics: microbial, chemical, and enzymatic aspects of the fungal attack of lignin

Wood is the main renewable material on Earth and is largely used as building material and in paper-pulp manufacturing. This review describes the composition of lignocellulosic materials, the different processes by which fungi are able to alter wood, including decay patterns caused by white, brown, and soft-rot fungi, and fungal staining of wood. The chemical, enzymatic, and molecular aspects of the fungal attack of lignin, which represents the key step in wood decay, are also discussed. Modern analytical techniques to investigate fungal degradation and modification of the lignin polymer are reviewed, as are the different oxidative enzymes (oxidoreductases) involved in lignin degradation. These include laccases, high redox potential ligninolytic peroxidases (lignin peroxidase, manganese peroxidase, and versatile peroxidase), and oxidases. Special emphasis is given to the reactions catalyzed, their synergistic action on lignin, and the structural bases for their unique catalytic properties. Broadening our knowledge of lignocellulose biodegradation processes should contribute to better control of wood-decaying fungi, as well as to the development of new biocatalysts of industrial interest based on these organisms and their enzymes. [Int Microbiol 2005; 8(3):195-204