1,650 research outputs found
Gamay grapevine peroxidase: Its role in vacuolar anthocyani(di)n degradation
The oxidation of anthocyani(di)ns by Gamay grapevine vacuolar peroxidases was studied. The results suggest that, unlike their glycosides, Gamay anthocyanins aglycones are degraded by peroxidases, the carbinol pseudobase probably being the true substrate, the oxidation of which was strictly dependent on H2O2. Only a weak substrate specificity was found in the H2O2-dependent degradation of peonidin, delphinidin and cyanidin. These results are discussed in the light of the subcellular localization of Gamay peroxidase, and of the possible involvement of this enzyme in anthocyanin turnover and degradation in planta.Rebperoxidase von Gamay: Ihre Rolle beim vakuolären Abbau von Anthocyani(di)nen.Die Oxidation von Anthocyani(di)nen durch vakuoläre Peroxidasen der Rebsorte Gamay wurde untersucht. Die Ergebnisse zeigen, daß - im Gegensatz zu ihren Glykosiden - die Anthocyanin-Aglykone durch Peroxidasen abgebaut werden, wobei wahrscheinlich die Carbinol-Pseudobase das eigentliche Substrat ist, dessen Oxidation von H2O2 abhängt. Beim H2O2-abhängigen Abbau von Päonidin, Delphinidin und Cyanidin wurde nur eine geringe Substratabhängigkeit gefunden. Die Ergebnisse werden im Zusammenhang mit der zellulären Lokalisierung der Gamay-Peroxidase und mit ihrer möglichen Rolle beim Anthocyaninmetabolismus in der Pflanze diskutiert
Epigenetic control of extracellular auxin catabolism in grapevine cells cultured in suspension
The several factors which control extracellular auxin catabolism were studied in grapevine (Vitis vinifera cv. Gamay), using cells cultured in suspension as a model system. From the results, it is concluded that, contrarily to previous observations with cultured cells, auxin catabolism in the spent medium depends on a massive sequential secretion of both basic and acidic isoperoxidases. It also depends on the secretion of phenolic compounds, characterized as of an 'auxin protector' nature, which modulate the IAA-oxidase activity of the extracellular isoperoxidases throughout the culture period. Thus, unlike observations of peroxidase activities, IAA-oxidase activities are expressed mainly during the beginning of the post-exponential growth phase of the cultured cells, giving to this highly compartmentalized catabolic process an apparent central role in the depletion of the IAA content, once the cultured cells have stopped growing
The specific expression of isoperoxidases in grapevine cells cultured in suspension in relation to vacuolar development
Die spezifischen Veränderungen der Isoperoxidasen in suspensionskultivierten Rebenzellen in Beziehung zur Entwicklung der ZellvakuoleAus wachsenden Beeren der Rotweinsorte Gamay (Vitis vinifera) wurden Zellsuspensionskulturen hergestellt. Diese dienten als Modellsystem, um die spezifischen Veränderungen der Enzymaktivität von Guajakol-Peroxidase und Indolyl-3-Essigsäure(IAA-)Oxidase während des Zellwachstums in Beziehung zur Entwicklung der Zellvakuole zu verfolgen. Der Entwicklungszustand der Vakuole wurde anhand des Verhältnisses monomere Anthocyane : Protein festgestellt. Die Untersuchungen zeigten, daß sich die Aktivität von Guajakol-Peroxidase während der exponentiellen Phase des Zellwachstums in Beziehung zum Entwicklungszustand der Vakuole veränderte. Andererseits wurde im Verlauf des Zellwachstums nie IAA-Oxidaseaktivität nachgewiesen, wahrscheinlich weil in den kultivierten Zellen höhere Konzentrationen von "Auxinprotektoren" vorhanden waren.Dieser Befund steht im Widerspruch zu der Beobachtung, daß die Zunahme der Gesamtperoxidasenaktivität in den Zellen in erster Linie auf den Anstieg der basischen Isoperoxidasen zurückzuführen ist. Aufgrund der Tatsache, daß der IAA-Abbau hauptsächlich durch basische Isoperoxidasen bewirkt wird, wird ferner die anerkannte physiologische Rolle der basischen Isoperoxidasen in suspensionskultivierten Zellen in Frage gestellt. Eine alternative Rolle, welche die basischen Isoperoxidasen im intensiven oxidativen Stoffwechsel der Phenole bei roten Rebsorten spielen könnten, wird diskutiert
Assessment of exposure to piroplasms in sheep grazing in communal mountain pastures by using a multiplex DNA bead-based suspension array
BACKGROUND: Piroplasms are tick-borne hemoprotozoans with a major impact on extensive management systems. Detection of sub-clinical low-level carriers, which can act as source of infection for vector ticks, is key to protect livestock trade and facilitate preventive control programs. The purpose of this study was to develop a method for the detection of ovine piroplasms and to use it in a field study aimed at investigating piroplasms infection in semi-extensive production systems in the Basque Country (northern Spain). METHODS: A DNA bead-based suspension array using the Luminex® xMAP technology that included a generic Theileria-Babesia control probe, 6 species-specific probes, and an internal control probe was developed to detect and identify piroplasms that infect sheep. To monitor piroplasm infection in clinically healthy sheep from 4 flocks that share communal mountain pastures, blood samples were collected during 2 grazing seasons. RESULTS: Piroplasms were detected in 48% (214/446) of blood samples, nearly half of them (49.1%, 105/214) as mixed infections. Five different piroplasms were identified: Theileria sp. OT3 in 34.8% of the samples, Theileria ovis in 20.9%, and at lower prevalences Babesia motasi (12.3%), Theileria luwenshuni/OT1 (10.5%) and Babesia ovis (6.3%). Despite differences among flocks associated to differences in management, an increasing trend in the incidence of piroplasm infection with increasing age of animals after increased tick exposure was observed. This increment could be attributed to continued re-infection associated with re-exposure to ticks at grazing. Ticks were collected from animals (4 species) and vegetation (8 species), and associations between tick abundance seasonality and risk of infection with the different piroplasms were established. CONCLUSION: The multiplex Luminex® xMAP procedure is a rapid and high throughput technique that provided highly specific and sensitive identification of single and mixed piroplasm infections in blood of sheep carriers. This study confirmed a situation of endemic stability for piroplasm infection in the region, where infection is present in the absence of clinical signs, and mountain grazing allows for sufficient inoculation rates to maintain such situation
Indicadores de calidad de la enseñanza universitaria: Una aproximación desde la perspectiva de los estudiantes
A Win–Win Combination to Inhibit Persistent Organic Pollutant Formation via the Co-Incineration of Polyvinyl Chloride E-Waste and Sewage Sludge
Persistent organic pollutant inhibition in the combustion process of polyvinyl chloride (PVC) by prior addition of an inhibitor is currently being studied, reducing the emission of pollutants, and thus reducing the large amount of waste PVC destined for landfill. In this work, the use of sewage sludge (SS) as an alternative to chemical inhibitors to improve the quality emissions of the incineration of polyvinyl chloride waste (PVC e-waste) was studied and optimized. Different combustion runs were carried out at 850 °C in a laboratory tubular reactor, varying both the molar ratio Ri (0.25, 0.50, 0.75) between inhibitors (N + S) and chlorine (Cl) and the oxygen ratio λ (0.15, 0.50) between actual oxygen and stoichiometric oxygen. The emissions of several semivolatile compounds families such as polycyclic aromatic hydrocarbons (PAHs), polychlorobenzenes (ClBzs), and polychlorophenols (ClPhs), with special interest in the emissions of the most toxic compounds, i.e., polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (dl-PCBs), were analyzed. A notable decrease in PCDD/F and dl-PCB formation was achieved in most of the experiments, especially for those runs performed under an oxygen-rich atmosphere (λ = 0.50), where the addition of sludge was beneficial with inhibition ratios Ri ≥ 0.25. An inhibition ratio of 0.75 showed the best results with almost a 100% reduction in PCDD/F formation and a 95% reduction in dl-PCB formation.Support for this work was granted by CTQ2016-76608-R project and the scholarship BES-2017-080382 from the Ministry of Economy, Industry and Competitiveness (Spain). GC-MS/QQQ used in the analysis was supported by Project IDIFEDER/2018/004 by the Generalitat Valenciana (Spain)
Probing the innermost regions of AGN jets and their magnetic fields with RadioAstron II. Observations of 3C 273 at minimum activity
RadioAstron is a 10 m orbiting radio telescope mounted on the Spektr-R
satellite, launched in 2011, performing Space Very Long Baseline Interferometry
(SVLBI) observations supported by a global ground array of radio telescopes.
With an apogee of about 350 000 km, it is offering for the first time the
possibility to perform {\mu}as-resolution imaging in the cm-band. We present
observations at 22 GHz of 3C 273, performed in 2014, designed to reach a
maximum baseline of approximately nine Earth diameters. Reaching an angular
resolution of 0.3 mas, we study a particularly low-activity state of the
source, and estimate the nuclear region brightness temperature, comparing with
the extreme one detected one year before during the RadioAstron early science
period. We also make use of the VLBA-BU-BLAZAR survey data, at 43 GHz, to study
the kinematics of the jet in a 1.5-year time window. We find that the nuclear
brightness temperature is two orders of magnitude lower than the exceptionally
high value detected in 2013 with RadioAstron at the same frequency (1.4x10^13
K, source-frame), and even one order of magnitude lower than the equipartition
value. The kinematics analysis at 43 GHz shows that a new component was ejected
2 months after the 2013 epoch, visible also in our 22 GHz map presented here.
Consequently this was located upstream of the core during the brightness
temperature peak. These observations confirm that the previously detected
extreme brightness temperature in 3C 273, exceeding the inverse Compton limit,
is a short-lived phenomenon caused by a temporary departure from equipartition.
Thus, the availability of interferometric baselines capable of providing
{\mu}as angular resolution does not systematically imply measured brightness
temperatures over the known physical limits for astrophysical sources.Comment: Accepted for publication in A&
BIG-DATA and the Challenges for Statistical Inference and Economics Teaching and Learning
The increasing automation in data collection, either in structured orunstructured formats, as well as the development of reading, concatenation and comparison algorithms and the growing analytical skills which characterize the era of Big Data, cannot not only be considered a technological achievement, but an organizational, methodological and analytical challenge for knowledge as well, which is necessary to generate opportunities and added value.In fact, exploiting the potential of Big-Data includes all fields of community activity; and given its ability to extract behaviour patterns, we are interested in the challenges for the field of teaching and learning, particularly in the field of statistical inference and economic theory.Big-Data can improve the understanding of concepts, models and techniques used in both statistical inference and economic theory, and it can also generate reliable and robust short and long term predictions. These facts have led to the demand for analytical capabilities, which in turn encourages teachers and students to demand access to massive information produced by individuals, companies and public and private organizations in their transactions and inter- relationships.Mass data (Big Data) is changing the way people access, understand and organize knowledge, which in turn is causing a shift in the approach to statistics and economics teaching, considering them as a real way of thinking rather than just operational and technical disciplines. Hence, the question is how teachers can use automated collection and analytical skills to their advantage when teaching statistics and economics; and whether it will lead to a change in what is taught and how it is taught.Peñaloza Figueroa, J.; Vargas Perez, C. (2017). BIG-DATA and the Challenges for Statistical Inference and Economics Teaching and Learning. Multidisciplinary Journal for Education, Social and Technological Sciences. 4(1):64-87. doi:10.4995/muse.2017.6350.SWORD648741Akerkar R. (Ed.). (2014). Big Data Computing. CRC Press.Anderson, C. (2009). "Living by Numbers". Wired Magazine. July 2009.New York: Conde Nast Publications.Cukier, Kenneth and Mayer-Schönberger, Viktor (2013). Big Data: A Revolution that Will Transform How We Live, Work and Think. John Murray Publishers. London, UK.Dean, J., & Ghemawat, S. (2008). MapReduce. Communications of the ACM, 51(1), 107. doi:10.1145/1327452.1327492Diebold, F. X. (2012). A Personal Perspective on the Origin(s) and Development of «Big Data»: The Phenomenon, the Term, and the Discipline, Second Version. SSRN Electronic Journal. doi:10.2139/ssrn.2202843Duboc, L., Rosenblum, D. S., & Wicks, T. (2006). A framework for modelling and analysis of software systems scalability. Proceeding of the 28th international conference on Software engineering - ICSE ’06. doi:10.1145/1134285.1134460García Ros, R., Pérez González, F. & Talaya González, I. (2008). Preferencias Respecto a Métodos Instruccionales de los Estudiantes Universitarios de Nuevo Acceso y su Relación con Estilos de Aprendizaje y Estrategias Motivacionales. Electronic Journal of Research in Educational Psychology, 6(16), 547-570.Gould, R. (2010). Statistics and the Modern Student. International Statistical Review, 78(2), 297-315. doi:10.1111/j.1751-5823.2010.00117.xKambatla, K., Kollias, G., Kumar, V., & Grama, A. (2014). Trends in big data analytics. Journal of Parallel and Distributed Computing, 74(7), 2561-2573. doi:10.1016/j.jpdc.2014.01.003Leedy, P. & Ormrod, J. (2001). Practical Research: Planning and Design. 7th Editon. Upper Saddle River, NJ: Merrill Prentice Hall. Thousand Oaks: SAGE Publications.Meyer-Schonberger, Viktor and Cukier, Kenneth (2013). Big Data: A Revolution that Will Transform How We Live, Work and Think. John Murray Publishers. London. UK Company.Müller, Martin U., Rosenbach, Marcel and Schulz, Thomas (2013). Living by Numbers: Big-Data Knows What your Future Holds. DER SPIEGEL No. 20. Germany (Translated from German by Christopher Sultan).Pe-a, D., Prieto, J. and Viladomat, J. (2010) "Eigenvectors of a Kurtosis Matrix as Interesting Directions to Reveal Cluster Structure", Journal of Multivariate Analysis 9, 1995 -2007, 2010. https://doi.org/10.4995/muse.2015.2245Peñaloza Figueroa, J. L., & Vargas Perez, C. (2014). Construction and Evaluation of Scenarios as a Learning Strategy through Modelling-Simulation. Multidisciplinary Journal for Education, Social and Technological Sciences, 2(1), 40. doi:10.4995/muse.2015.2245Zhang, J., Wang, F.-Y., Wang, K., Lin, W.-H., Xu, X., & Chen, C. (2011). Data-Driven Intelligent Transportation Systems: A Survey. IEEE Transactions on Intelligent Transportation Systems, 12(4), 1624-1639. doi:10.1109/tits.2011.215800
Emergence of coherent motion in aggregates of motile coupled maps
In this paper we study the emergence of coherence in collective motion
described by a system of interacting motiles endowed with an inner, adaptative,
steering mechanism. By means of a nonlinear parametric coupling, the system
elements are able to swing along the route to chaos. Thereby, each motile can
display different types of behavior, i.e. from ordered to fully erratic motion,
accordingly with its surrounding conditions. The appearance of patterns of
collective motion is shown to be related to the emergence of interparticle
synchronization and the degree of coherence of motion is quantified by means of
a graph representation. The effects related to the density of particles and to
interparticle distances are explored. It is shown that the higher degrees of
coherence and group cohesion are attained when the system elements display a
combination of ordered and chaotic behaviors, which emerges from a collective
self-organization process.Comment: 33 pages, 12 figures, accepted for publication at Chaos, Solitons and
Fractal
Influencia del riego deficitario controlado precosecha sobre la calidad de la cereza ´Prime Giant`
El uso de redes de sensores para el manejo del riego deficitario controlado (RDC) en
cerezo puede incidir en la mejora de la productividad del agua, calidad de la fruta y en su
comportamiento poscosecha, al permitir el conocimiento y control del estado hídrico del
suelo y árbol en todo momento.
En el primer año de ensayo, el riego deficitario aplicado en precosecha para
satisfacer el 85% de las necesidades máximas del cultivo (ETcg) permitió un ahorro de agua
del 17% (380 m3 ha-1) respecto al tratamiento control, que se regó al 110% de la ETcg. Este
déficit hídrico ligero no afectó a la producción (16,13 t ha-1) e incluso mejoró la calidad del
fruto. Así, en el momento de la cosecha (t0) los frutos bajo déficit ligero presentaron matices
más rojos y mayor acidez que los de riego completo. Esta mayor acidez no afectó al índice
de madurez debido a la compensación por sólidos solubles totales (SST). El carácter de
mayor acidez perduró tras 30 días de conservación en frio (t1) y 5 días de simulación de las
condiciones de comercialización (t2). Igualmente, los frutos bajo déficit hídrico presentaron
una tendencia a menores pérdidas de peso por deshidratación a finales de los periodos de
conservación en frio y de simulación de la comercialización.Ministerio de Economía y Competitividad AGL2013-49047-C2-1
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