766 research outputs found

    Economic and social impacts of logging at national forests - a study case at Brazil

    Get PDF
    Brazil has the largest tropical rainforests in the world and most of them are located at Amazon River basin area. During the last three decades, deforestation are growing very fast in this region, having negative impacts at local and global weather. In order to minimize these impacts and protect part of the biodiversity, Brazilian government established several national forests in this area, but just one have being explored, the Tapajós National Forest (known as Flona Tapajós). This paper evaluates the economic and social features of a reduced impact logging project conducted at Flona Tapajós from 1999 to 2003. It was coordinated by IBAMA (the Brazilian governmental agency responsible for managing National Forests), funded by ITTO (International Tropical Timber Organization) and conducted by Treviso Agropecuária Ltda (a private enterprise). This project is locally known as ITTO project. Basing on field interviews and examining IBAMA´s and Treviso´s documents, this paper concludes that ITTO project was highly profitable for the private company, in spite of the company had obeyed all Brazilian working laws, what is not very common at this Brazilian region. Treviso´s internal rate of return was 35.79%. ITTO project impacted significantly the community workers involved with the project and it was able to teach this population how to manage rainforests in order to produce timber without destroying them. The paper ends by suggesting some attitudes that Brazilian government can follow in its discussion about new reduced impact logging projects to be implemented at Flona Tapajós and other national forests by both private enterprises and local communities.

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

    Get PDF
    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

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

    Full text link
    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

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

    Full text link
    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

    Survival and Clinical Course at Fontan After Stage One Palliation With Either a Modified Blalock-Taussig Shunt or a Right Ventricle to Pulmonary Artery Conduit

    Get PDF
    ObjectivesWe sought to determine whether the type of shunt used at stage one palliation (S1P) affected the survival and the perioperative course through Fontan completion.BackgroundAlthough improved surgical and interstage survival have been demonstrated with the use of the right ventricle to pulmonary artery (RV-PA) conduit compared with a modified Blalock-Taussig shunt (BTS) at S1P, it is unknown whether this effect will be observed in long-term follow-up.MethodsAll patients who underwent a S1P during 2002 and 2003 (n = 80) at our institution were included for analysis. Patients were followed until death or June 1, 2007. Perioperative variables at Fontan completion were recorded.ResultsFor the entire cohort, cumulative survival for those who underwent a RV-PA conduit (n = 34) was 79.4% at 3 years compared with 65.8% in the modified BTS group (n = 46) (log-rank = 0.31). At Fontan (n = 44), when compared with those who had received a modified BTS, those who had a RV-PA conduit placed at S1P had no difference in the median duration of ventilation (21 h [range 10 to 96 h] vs. 26.5 h [range 7 to 204 h], p = 0.09) or hospital stay (9 days [range 5 to 29 days] vs. 10 days [range 6 to 48 days], p = 0.89), although length of stay in the intensive care unit was shorter (2 days [range 0 to 6 days] vs. 4 days [range 1 to 25 days], p = 0.01). Sixty-seven percent of the RV-PA conduit group had at least one PA intervention 3 years after S1P compared with 42.8% in the modified BTS group (log-rank = 0.11).ConclusionsNonstatistically significant trends toward improved cumulative survival and increased PA interventions were demonstrated in patients who had a RV-PA conduit placed at S1P. Longitudinal follow-up of larger groups of randomized patients is required to determine the influence of the RV-PA conduit on long-term outcomes
    corecore