85 research outputs found

    Alcances e obstáculos do accountability midiático na América Latina após a Terceira Onda da Democratização

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    Una de las más clásicas funciones normativas de los medios de comunicación en las democracias es la de ser vigilantes del poder, tanto para servir como defensores de la ciudadanía como para que la opinión pública tome correctas decisiones. El presente trabajo discute desde una posición crítica la accountability mediática en América Latina tras la Tercera Ola de la Democracia hasta el presente, la que si bien ha tenido una importante labor denunciante e investigativa en determinados casos de corrupción política, se postula como limitada por dos razones: la primera, la alta concentración de la propiedad de los sistemas de medios regionales ha provocado un bajo pluralismo informativo que puede poner en duda los verdaderos alcances e intenciones de la vigilancia que realizan los medios al poder y su aporte a las democracias. Por otra parte, y como segunda razón, las reformas de los últimos años llevadas a cabo por algunos gobiernos de liderazgo progresista o populista no han creado un ambiente propicio para esta función, al contrario, han propiciado carencias para la libertad informativa, principio básico para la accountability mediática. A modo de conclusión, se reflexiona sobre la importancia de fomentar el pluralismo informativo y la libertad de expresión como bases para la vigilancia de los medios al poder en la región latinoamericana.One of the most classic normative functions of media in democracies is to be vigilant of power, both to serve as defenders of the citizens and for the public opinion to make correct decisions. This paper discusses from a critical perspective the accountability of the media in Latin America from the Third Wave of Democracy up to date, which has been important in denouncing and investigating certain cases of political corruption, but has been limited for two reasons: the first is the high concentration of ownership of regional media systems, have led to a very low level of informative pluralism which calls into question the true scope and intentions of the surveillance that the media can carry out of power and its contribution to democracy. On the other hand, the second reason is the reforms carried out in recent years by the leadership of some progressive or populist governments that have not created a proper environment for this function, and on the contrary, have provided shortcomings for the freedom of information, a basic principle for media accountability. As a conclusion, this paper reflects on the importance of promoting informative pluralism and freedom of expression as the basis of media surveillance of power in the Latin American region.Uma das mais clássicas funções normativas dos meios de comunicação nas democracias é a de ser vigilantes do poder, tanto para servir como defensores da cidadania quanto para que a opinião pública tome decisões corretas. Este trabalho discute, sob uma posição crítica, o accountability midiático na América Latina após a Terceira Onda da Democratização até o presente, a que, embora tenha tido um importante trabalho denunciante e investigativo em determinados casos de corrupção política, apresenta-se como limitada por duas razões: a alta concentração da propriedade dos sistemas de meios regionais que provoca um baixo pluralismo informativo que pode colocar em dúvida os verdadeiros alcances e intenções da vigilância realizados pelos meios ao poder e sua contribuição para a democracia; por outro lado, e como segunda razão, as reformas dos últimos anos realizadas por alguns governos de liderança progressista ou populista que não criaram um ambiente propício para essa função; ao contrário, promoveram carências para a liberdade informativa, princípio básico para o accountability midiático. Como conclusão, reflexiona-se sobre a importância de fomentar o pluralismo informativo e a liberdade de expressão como bases para a vigilância dos meios ao poder na região latino-americana.https://revistas.udem.edu.co/index.php/anagramas/article/view/194

    Constraints on Nucleon Decay via "Invisible" Modes from the Sudbury Neutrino Observatory

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    Data from the Sudbury Neutrino Observatory have been used to constrain the lifetime for nucleon decay to ``invisible'' modes, such as n -> 3 nu. The analysis was based on a search for gamma-rays from the de-excitation of the residual nucleus that would result from the disappearance of either a proton or neutron from O16. A limit of tau_inv > 2 x 10^{29} years is obtained at 90% confidence for either neutron or proton decay modes. This is about an order of magnitude more stringent than previous constraints on invisible proton decay modes and 400 times more stringent than similar neutron modes.Comment: Update includes missing efficiency factor (limits change by factor of 2) Submitted to Physical Review Letter

    Denitrification likely catalyzed by endobionts in an allogromiid foraminifer

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    Author Posting. © The Author(s), 2011. This is the author's version of the work. It is posted here by permission of Nature Publishing Group for personal use, not for redistribution. The definitive version was published in The ISME Journal 6 (2012): 951–960, doi:10.1038/ismej.2011.171.Nitrogen can be a limiting macronutrient for carbon uptake by the marine biosphere. The process of denitrification (conversion of nitrate to gaseous compounds, including N2) removes bioavailable nitrogen, particularly in marine sediments, making it a key factor in the marine nitrogen budget. Benthic foraminifera reportedly perform complete denitrification, a process previously considered nearly exclusively performed by bacteria and archaea. If the ability to denitrify is widespread among these diverse and abundant protists, a paradigm shift is required for biogeochemistry and marine microbial ecology. However, to date, the mechanisms of foraminiferal denitrification are unclear and it is possible that the ability to perform complete denitrification is due to symbiont metabolism in some foraminiferal species. Using sequence analysis and GeneFISH, we show that for a symbiont-bearing foraminifer, the potential for denitrification resides in the endobionts. Results also identify the endobionts as denitrifying pseudomonads and show that the allogromiid accumulates nitrate intracellularly, presumably for use in denitrification. Endobionts have been observed within many foraminiferal species, and in the case of associations with denitrifying bacteria, may provide fitness for survival in anoxic conditions. These associations may have been a driving force for early foraminiferal diversification, which is thought to have occurred in the Neoproterozoic when anoxia was widespread.This research was supported by NSF grant EF-0702491 to JMB, KLC and VPE; some ship support was provided by NSF MCB-0604084 to VPE and JMB.2012-06-0

    First Neutrino Observations from the Sudbury Neutrino Observatory

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    The first neutrino observations from the Sudbury Neutrino Observatory are presented from preliminary analyses. Based on energy, direction and location, the data in the region of interest appear to be dominated by 8B solar neutrinos, detected by the charged current reaction on deuterium and elastic scattering from electrons, with very little background. Measurements of radioactive backgrounds indicate that the measurement of all active neutrino types via the neutral current reaction on deuterium will be possible with small systematic uncertainties. Quantitative results for the fluxes observed with these reactions will be provided when further calibrations have been completed.Comment: Latex, 7 pages, 10 figures, Invited paper at Neutrino 2000 Conference, Sudbury, Canada, June 16-21, 2000 to be published in the Proceeding

    Major agricultural changes required to mitigate phosphorus losses under climate change

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    Phosphorus losses from land to water will be impacted by climate change and land management for food production, with detrimental impacts on aquatic ecosystems. Here we use a unique combination of methods to evaluate the impact of projected climate change on future phosphorus transfers, and to assess what scale of agricultural change would be needed to mitigate these transfers. We combine novel high-frequency phosphorus flux data from three representative catchments across the UK, a new high-spatial resolution climate model, uncertainty estimates from an ensemble of future climate simulations, two phosphorus transfer models of contrasting complexity and a simplified representation of the potential intensification of agriculture based on expert elicitation from land managers. We show that the effect of climate change on average winter phosphorus loads (predicted increase up to 30% by 2050s) will be limited only by large-scale agricultural changes (e.g., 20–80% reduction in phosphorus inputs)

    Characterization and quantification of ammonia-oxidizing archaea (AOA) and bacteria (AOB) in a nitrogen-removing reactor using T-RFLP and qPCR

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    Using ammonia monooxygenase α-subunit (amoA) gene and 16S rRNA gene, the community structure and abundance of ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB) in a nitrogen-removing reactor, which was operated for five phases, were characterized and quantified by cloning, terminal restriction fragment length polymorphism (T-RFLP), and quantitative polymerase chain reaction (qPCR). The results suggested that the dominant AOB in the reactor fell to the genus Nitrosomonas, while the dominant AOA belonged to Crenarchaeotal Group I.1a in phylum Crenarchaeota. Real-time PCR results demonstrated that the levels of AOB amoA varied from 2.9 × 103 to 2.3 × 105 copies per nanogram DNA, greatly (about 60 times) higher than those of AOA, which ranged from 1.7 × 102 to 3.8 × 103 copies per nanogram DNA. This indicated the possible leading role of AOB in the nitrification process in this study. T-RFLP results showed that the AOB community structure significantly shifted in different phases while AOA only showed one major peak for all the phases. The analyses also suggested that the AOB community was more sensitive than that of AOA to operational conditions, such as ammonia loading and dissolved oxygen

    Cross-sectional analysis of baseline differences of candidates for rotator cuff surgery: a sex and gender perspective

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    <p>Abstract</p> <p>Background</p> <p>The word "sex" refers to biological differences between men and women. Gender refers to roles, behaviors, activities, and attributes that a given society considers appropriate for men and women. Traditionally, treatment decisions have been based on patient's sex without including the gender. Assessment of disability secondary to musculoskeletal problems would not be complete or accurate unless potentially relevant biological and non-biological aspects of being a man or woman are taken into consideration. The purposes of this study were to: 1) investigate the difference in pre-operative characteristics between men and women who were candidates for rotator cuff surgery; and, 2) assess the relationship between level of disability and factors that represent sex and factors that signify gender.</p> <p>Method</p> <p>This was a cross-sectional study. The primary outcome measure of disability was a disease-specific outcome measure, the Western Ontario Rotator Cuff (WORC) index, and independent variables were sex, age, hand dominance, shoulder side involvement, BMI, co-morbidity, medication use, work status, smoking habits, strength, range of motion, level of pathology, concurrent osteoarthritis, expectations for recovery, and participation restriction. Parametric, non-parametric, univariable, subgroup, and multivariable analyses were conducted.</p> <p>Results</p> <p>One hundred and seventy patients were included in the study. The mean age was 57 ± 11, 85 were females. Women reported higher levels of disability despite similar or lower levels of pathology. Scores of the WORC were strongly influenced by factors that represented "gender" such as participation restriction (F = 28.91, p < 0.0001) and expectations for improved activities of daily living (F = 5.80, p = 0.004). Painfree combined range of motion, which represented an interaction between "sex" and "gender" was also associated with disability after being adjusted for all other relevant baseline factors (F = 25.82, p < 0.0001).</p> <p>Conclusion</p> <p>Gender-related factors such as expectations and participation limitations have an independent impact on disability in men and women undergoing rotator cuff related surgery.</p

    Changes in N-Transforming Archaea and Bacteria in Soil during the Establishment of Bioenergy Crops

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    Widespread adaptation of biomass production for bioenergy may influence important biogeochemical functions in the landscape, which are mainly carried out by soil microbes. Here we explore the impact of four potential bioenergy feedstock crops (maize, switchgrass, Miscanthus X giganteus, and mixed tallgrass prairie) on nitrogen cycling microorganisms in the soil by monitoring the changes in the quantity (real-time PCR) and diversity (barcoded pyrosequencing) of key functional genes (nifH, bacterial/archaeal amoA and nosZ) and 16S rRNA genes over two years after bioenergy crop establishment. The quantities of these N-cycling genes were relatively stable in all four crops, except maize (the only fertilized crop), in which the population size of AOB doubled in less than 3 months. The nitrification rate was significantly correlated with the quantity of ammonia-oxidizing archaea (AOA) not bacteria (AOB), indicating that archaea were the major ammonia oxidizers. Deep sequencing revealed high diversity of nifH, archaeal amoA, bacterial amoA, nosZ and 16S rRNA genes, with 229, 309, 330, 331 and 8989 OTUs observed, respectively. Rarefaction analysis revealed the diversity of archaeal amoA in maize markedly decreased in the second year. Ordination analysis of T-RFLP and pyrosequencing results showed that the N-transforming microbial community structures in the soil under these crops gradually differentiated. Thus far, our two-year study has shown that specific N-transforming microbial communities develop in the soil in response to planting different bioenergy crops, and each functional group responded in a different way. Our results also suggest that cultivation of maize with N-fertilization increases the abundance of AOB and denitrifiers, reduces the diversity of AOA, and results in significant changes in the structure of denitrification community
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