549 research outputs found

    SCSBRS 113 - Tio Taka: cultivar de arroz irrigado obtida através de seleção recorrente.

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    O objetivo deste trabalho é mostrar e discutir os principais resultados que levaram ao lançamento da SCSBRS 113 ? TioTaka para plantio em Santa Catarina e apresentar a metodologia utilizada no desenvolvimento da referida cultivar

    Ergosterol Effect on the Desaturation of 14C-Cis-Vaccenate in Tetrahymena

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    Supplement of ergosterol to the growth medium of the ciliated protozoan Tetrahymena pyriformis W leads to incorporation of the foreign sterol within cell membranes and suppression of synthesis of the native sterol-like compound tetrahymanol, as well as to changes in the fatty acid compositions of several major classes of membrane lipid. Alteration of fatty acid composition is thought to represent a regulatory mechanism whereby optimum membrane fluidity is maintained when the slightly dissimilar foreign sterol is added into the phospholipid bilayer of the membranes. The present study, using several different conditions of growth temperature, substrate concentrations and incubation time, and ergosterol concentrations and exposure time, is an attempt to provide evidence supporting a hypothetical regulatory mechanism. This mechanism proposes that there is a feedback regulation by membrane-bound sterol on an enzyme or enzymes involved in synthesis of the long chain fatty acids contained in membrane phospholipid. Such a mechanism could account for the balance between sterol and fatty acid content of membrane. The data presented here show that a statistically significant increase in desaturation of 14C-cis-vaccenate can be demonstrated in Tetrahymena cell cultures whose membranes contain the foreign sterol, when growth temperature is maintained at 20° or 29.5°. Tetrahymena desaturated 14C-cis-vaccenate substrate in both ergosterol supplemented and normal cultures. The 14C labeled product, 6,11-18:2 was recovered and separated by silver nitrate-Unisil column chromatography

    Holonomic functions of several complex variables and singularities of anisotropic Ising n-fold integrals

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    Lattice statistical mechanics, often provides a natural (holonomic) framework to perform singularity analysis with several complex variables that would, in a general mathematical framework, be too complex, or could not be defined. Considering several Picard-Fuchs systems of two-variables "above" Calabi-Yau ODEs, associated with double hypergeometric series, we show that holonomic functions are actually a good framework for actually finding the singular manifolds. We, then, analyse the singular algebraic varieties of the n-fold integrals χ(n) \chi^{(n)}, corresponding to the decomposition of the magnetic susceptibility of the anisotropic square Ising model. We revisit a set of Nickelian singularities that turns out to be a two-parameter family of elliptic curves. We then find a first set of non-Nickelian singularities for χ(3) \chi^{(3)} and χ(4) \chi^{(4)}, that also turns out to be rational or ellipic curves. We underline the fact that these singular curves depend on the anisotropy of the Ising model. We address, from a birational viewpoint, the emergence of families of elliptic curves, and of Calabi-Yau manifolds on such problems. We discuss the accumulation of these singular curves for the non-holonomic anisotropic full susceptibility.Comment: 36 page

    Political candidates in infotainment programmes and their emotional effects on Twitter: An analysis of the 2015 Spanish general elections pre-campaign season

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    This is an Accepted Manuscript of an article published by Taylor & Francis in Contemporary Social Science on 2019, available online: http://www.tandfonline.com/10.1080/21582041.2017.1367833.[EN] The infotainment format offers candidates an informal setting to show a more personal side of themselves to the electorate, opening themselves up to potential voters. An example of media hybridisation, social networks users can immediately comment on infotainment television programmes, a process known as second screening. These second screeners tend to be especially active in politics. This paper analyses the immediate emotional reaction of these users as they watch infotainment programmes that air during the campaign or pre-campaign seasons and feature political candidates as guests. We have confirmed that second screeners react more emotionally towards the candidate when his or her party is mentioned, and less emotionally when the host displays an aggressive attitude through his or her non-verbal communication. When issues related to the candidate¿s personal lives are discussed, users¿ emotional reactions improve slightly. The relevance of this research stems from the fact that we are witnessing the consolidation of a politics that increasingly strays from ideological questions, and instead focuses on more emotional and personal issues.This work was supported by the Ministerio de Economia y Competitividad under Grants CSO2013-43960-R and CSO2016-77331-C2-1-R.Baviera, T.; Peris, À.; Cano-Orón, L. (2019). Political candidates in infotainment programmes and their emotional effects on Twitter: An analysis of the 2015 Spanish general elections pre-campaign season. Contemporary Social Science. 14(1):144-156. https://doi.org/10.1080/21582041.2017.1367833S144156141Baum, M. A., & Jamison, A. S. (2006). TheOprahEffect: How Soft News Helps Inattentive Citizens Vote Consistently. The Journal of Politics, 68(4), 946-959. doi:10.1111/j.1468-2508.2006.00482.xBravo-Marquez, F., Mendoza, M., & Poblete, B. (2014). Meta-level sentiment models for big social data analysis. Knowledge-Based Systems, 69, 86-99. doi:10.1016/j.knosys.2014.05.016Casero-Ripollés, A., Feenstra, R. A., & Tormey, S. (2016). Old and New Media Logics in an Electoral Campaign. The International Journal of Press/Politics, 21(3), 378-397. doi:10.1177/1940161216645340Ceron, A., & Splendore, S. (2016). From contents to comments: Social TV and perceived pluralism in political talk shows. New Media & Society, 20(2), 659-675. doi:10.1177/1461444816668187Chadwick, A. (2013). The Hybrid Media System. doi:10.1093/acprof:oso/9780199759477.001.0001Dang-Xuan, L., Stieglitz, S., Wladarsch, J., & Neuberger, C. (2013). AN INVESTIGATION OF INFLUENTIALS AND THE ROLE OF SENTIMENT IN POLITICAL COMMUNICATION ON TWITTER DURING ELECTION PERIODS. Information, Communication & Society, 16(5), 795-825. doi:10.1080/1369118x.2013.783608Giglietto, F., & Selva, D. (2014). Second Screen and Participation: A Content Analysis on a Full Season Dataset of Tweets. Journal of Communication, 64(2), 260-277. doi:10.1111/jcom.12085Grabe, M. E., & Bucy, E. P. (2009). Image Bite Politics. doi:10.1093/acprof:oso/9780195372076.001.0001Guo, L., & Vargo, C. (2015). The Power of Message Networks: A Big-Data Analysis of the Network Agenda Setting Model and Issue Ownership. Mass Communication and Society, 18(5), 557-576. doi:10.1080/15205436.2015.1045300Harrington, S. (2008). Popular news in the 21st century Time for a new critical approach? Journalism: Theory, Practice & Criticism, 9(3), 266-284. doi:10.1177/1464884907089008López-Rico, C.-M., & Peris-Blanes, À. (2017). Agenda e imagen de los candidatos de las elecciones generales de 2015 en España en programas televisivos de infoentretenimiento. El Profesional de la Información, 26(4), 611. doi:10.3145/epi.2017.jul.05Maruyama, M., Robertson, S. P., Douglas, S., Raine, R., & Semaan, B. (2017). Social Watching a Civic Broadcast. Proceedings of the 2017 ACM Conference on Computer Supported Cooperative Work and Social Computing. doi:10.1145/2998181.2998340Medhat, W., Hassan, A., & Korashy, H. (2014). Sentiment analysis algorithms and applications: A survey. Ain Shams Engineering Journal, 5(4), 1093-1113. doi:10.1016/j.asej.2014.04.011Saif, H., He, Y., & Alani, H. (2012). Semantic Sentiment Analysis of Twitter. Lecture Notes in Computer Science, 508-524. doi:10.1007/978-3-642-35176-1_32Shah, D. V., Hanna, A., Bucy, E. P., Lassen, D. S., Van Thomme, J., Bialik, K., … Pevehouse, J. C. W. (2016). Dual Screening During Presidential Debates. American Behavioral Scientist, 60(14), 1816-1843. doi:10.1177/0002764216676245Sullivan, D. G., & Masters, R. D. (1988). «Happy Warriors»: Leaders’ Facial Displays, Viewers’ Emotions, and Political Support. American Journal of Political Science, 32(2), 345. doi:10.2307/2111127Thelwall, M., Buckley, K., Paltoglou, G., Cai, D., & Kappas, A. (2010). Sentiment strength detection in short informal text. Journal of the American Society for Information Science and Technology, 61(12), 2544-2558. doi:10.1002/asi.21416Vergeer, M., & Franses, P. H. (2015). Live audience responses to live televised election debates: time series analysis of issue salience and party salience on audience behavior. Information, Communication & Society, 19(10), 1390-1410. doi:10.1080/1369118x.2015.1093526Vilares, D., Thelwall, M., & Alonso, M. A. (2015). The megaphone of the people? Spanish SentiStrength for real-time analysis of political tweets. Journal of Information Science, 41(6), 799-813. doi:10.1177/0165551515598926Wohn, D. Y., & Na, E.-K. (2011). Tweeting about TV: Sharing television viewing experiences via social media message streams. First Monday. doi:10.5210/fm.v16i3.336

    1 - hidrĂłxi - 4 - oxo - 2,5 - ciclohexadieno - 1 - acetato de etila em Jacaranda mimosaefolia D. Don - Bignoniaceae

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    1-hydroxy-4-oxo-2,5-ciclohadien-1-ethyl acetate has been isolated from leaves and fruits of Jacaranda mimosaefolia D. Don, Bignoniaceae growing in Rio Grande do Sul, Brasil.Cromatografia em camada delgada de um extrato de Jacarada mimosaefolia D. Don mostrou a presença de 1-hidróxi-4-oxo-2,5-ciclohexadieno-1-acetato de etila nas folhas e frutos do vegetal.

    Isolamento de gnafalina a partir de Achyrocline alata (HBK) D. C.

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    A flavonoid was isolated from flowering stems of Achyrocline alata and structure was assigned to it by comparison with an authentic sample of 5-hydroxy-7, 8-dimethoxy-favonol.Dos caules floridos de Achyrocline alata foi isolado um flavonoide e a sua estrutura foi determinada por comparação com amostra autêntica de 5-hidroxi-7, 8-dimetoxi-flavonol

    Stellar coronal astronomy - a review

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    Coronal astronomy is by now a fairly mature discipline, with a quarter century having gone by since the detection of the first stellar X-ray coronal source (Capella), and having benefitted from a series of major orbiting observing facilities. Several observational characteristics of coronal X-ray and EUV emission have been solidly established through extensive observations, and are by now common, almost text-book, knowledge. At the same time the implications of coronal astronomy for broader astrophysical questions (e.g. Galactic structure, stellar formation, stellar structure, etc.) have become appreciated. The interpretation of stellar coronal properties is however still often open to debate, and will need qualitatively new observational data to book further progress. In the present review we try to recapitulate our view on the status of the field at the beginning of a new era, in which the high sensitivity and the high spectral resolution provided by Chandra and XMM-Newton will address new questions which were not accessible before.Comment: Space Science Reviews, in press, 132 pages (full paper available at ftp://astro.esa.int/pub/ffavata/Papers/ssr-preprint.pdf
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