22 research outputs found

    Luminescence characteristics of quartz from Brazilian sediments and constraints for OSL dating

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    This study analyzes the optically stimulated luminescence (OSL) characteristics of quartz grains from fluvial, eolian and shallow marine sands of northeastern and southeastern Brazil, with especial focus on the applicability of the single-aliquot regenerative dose (SAR) dating protocol. All analyzed Brazilian sediments presented relatively high OSL sensitivity and good behavior regarding their luminescence characteristics relevant for radiation dose estimation. However, some samples from the Lençóis Maranhenses region in northeastern Brazil showed inadequate OSL sensitivity correction, hampering the implementation of the SAR protocol and their ability to behave as a natural dosimeter. While the shallow marine and eolian samples showed a narrow and reliable dose distribution, the fluvial sample had a wide dose distribution, suggesting incomplete bleaching and natural doses estimates dependent on age models

    Communication for Peaceful Social Change and Global Citizenry

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    The adoption of the 17 Sustainable Development Goals (SDGs) by the United Nations (UN) in 2015 represents a universal call to action involving multiple international actors for the purpose of eradicating poverty, improving living conditions and promoting peace. This entry provides a theoretical overview of the contributions of scholars and practitioners who highlight the importance of a transformative, educational and emancipatory communication by different social actors to establish the main lines of action for the 2030 Agenda for Sustainable Development. This communicative model involves the coordination of actors and strategies, both short- and long-term, cross-cutting actions and discourses to build social, cultural and political settings based on the criteria of peace, equality, social justice and human rights. Specifically, this entails a contribution to the objectives set out in SDG 16, “Peace, Justice and Strong Institutions”, given that the proposed theoretical framework is grounded in Communication for Peace and Communication for Social Change, and includes a systematization of different strategies and experiences from a variety of social issuers, mainly institutions, non-governmental organizations (NGOs) or social movements, aimed at promoting peaceful and inclusive societies. Specifically, communication for peaceful social change and global citizenry contributes to the achievement of specific SDG 16 objectives, particularly 16.1: Significantly reduce all forms of violence... [...

    NEOTROPICAL XENARTHRANS: a data set of occurrence of xenarthran species in the Neotropics

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    Xenarthrans – anteaters, sloths, and armadillos – have essential functions for ecosystem maintenance, such as insect control and nutrient cycling, playing key roles as ecosystem engineers. Because of habitat loss and fragmentation, hunting pressure, and conflicts with 24 domestic dogs, these species have been threatened locally, regionally, or even across their full distribution ranges. The Neotropics harbor 21 species of armadillos, ten anteaters, and six sloths. Our dataset includes the families Chlamyphoridae (13), Dasypodidae (7), Myrmecophagidae (3), Bradypodidae (4), and Megalonychidae (2). We have no occurrence data on Dasypus pilosus (Dasypodidae). Regarding Cyclopedidae, until recently, only one species was recognized, but new genetic studies have revealed that the group is represented by seven species. In this data-paper, we compiled a total of 42,528 records of 31 species, represented by occurrence and quantitative data, totaling 24,847 unique georeferenced records. The geographic range is from the south of the USA, Mexico, and Caribbean countries at the northern portion of the Neotropics, to its austral distribution in Argentina, Paraguay, Chile, and Uruguay. Regarding anteaters, Myrmecophaga tridactyla has the most records (n=5,941), and Cyclopes sp. has the fewest (n=240). The armadillo species with the most data is Dasypus novemcinctus (n=11,588), and the least recorded for Calyptophractus retusus (n=33). With regards to sloth species, Bradypus variegatus has the most records (n=962), and Bradypus pygmaeus has the fewest (n=12). Our main objective with Neotropical Xenarthrans is to make occurrence and quantitative data available to facilitate more ecological research, particularly if we integrate the xenarthran data with other datasets of Neotropical Series which will become available very soon (i.e. Neotropical Carnivores, Neotropical Invasive Mammals, and Neotropical Hunters and Dogs). Therefore, studies on trophic cascades, hunting pressure, habitat loss, fragmentation effects, species invasion, and climate change effects will be possible with the Neotropical Xenarthrans dataset

    Media democratization in Brazil: achievements and future challenges

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    This article focuses on the achievements in the field of media democratization in Brazil, underlining the current challenges that public communication systems face in the light of the persistence of the misuse of these structures by politicians for their own interests. The role that the public media platform can have in the democratic project is examined, including how it can assist policymakers concerning vital national as well as global issues. The slow democratization of Brazil during recent decades, however, has taken place while not altogether disassociated from the authoritarian legacy that has characterized the formation of Brazilian society. Nonetheless, the acknowledgement that the mainstream media have become more professional, including wider voices in the mediated sphere, is not reason enough to proclaim the end of the struggles for media democratization
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