18 research outputs found

    Analyzing the Strategy of Propaganda using Inverse Reinforcement Learning: Evidence from the 2022 Russian Invasion of Ukraine

    Full text link
    The 2022 Russian invasion of Ukraine was accompanied by a large-scale, pro-Russian propaganda campaign on social media. However, the strategy behind the dissemination of propaganda has remained unclear, particularly how the online discourse was strategically shaped by the propagandists' community. Here, we analyze the strategy of the Twitter community using an inverse reinforcement learning (IRL) approach. Specifically, IRL allows us to model online behavior as a Markov decision process, where the goal is to infer the underlying reward structure that guides propagandists when interacting with users with a supporting or opposing stance toward the invasion. Thereby, we aim to understand empirically whether and how between-user interactions are strategically used to promote the proliferation of Russian propaganda. For this, we leverage a large-scale dataset with 349,455 posts with pro-Russian propaganda from 132,131 users. We show that bots and humans follow a different strategy: bots respond predominantly to pro-invasion messages, suggesting that they seek to drive virality; while messages indicating opposition primarily elicit responses from humans, suggesting that they tend to engage in critical discussions. To the best of our knowledge, this is the first study analyzing the strategy behind propaganda from the 2022 Russian invasion of Ukraine through the lens of IRL

    Causal Understanding of Why Users Share Hate Speech on Social Media

    Full text link
    Hate speech on social media threatens the mental and physical well-being of individuals and is further responsible for real-world violence. An important driver behind the spread of hate speech and thus why hateful posts can go viral are reshares, yet little is known about why users reshare hate speech. In this paper, we present a comprehensive, causal analysis of the user attributes that make users reshare hate speech. However, causal inference from observational social media data is challenging, because such data likely suffer from selection bias, and there is further confounding due to differences in the vulnerability of users to hate speech. We develop a novel, three-step causal framework: (1) We debias the observational social media data by applying inverse propensity scoring. (2) We use the debiased propensity scores to model the latent vulnerability of users to hate speech as a latent embedding. (3) We model the causal effects of user attributes on users' probability of sharing hate speech, while controlling for the latent vulnerability of users to hate speech. Compared to existing baselines, a particular strength of our framework is that it models causal effects that are non-linear, yet still explainable. We find that users with fewer followers, fewer friends, and fewer posts share more hate speech. Younger accounts, in return, share less hate speech. Overall, understanding the factors that drive users to share hate speech is crucial for detecting individuals at risk of engaging in harmful behavior and for designing effective mitigation strategies

    Russian propaganda on social media during the 2022 invasion of Ukraine

    Full text link
    The Russian invasion of Ukraine in February 2022 was accompanied by a large-scale propaganda campaign. Here, we analyze the spread of Russian propaganda on social media. For this, we collected N = 349,455 messages from Twitter with pro-Russian content. Our findings suggest that pro-Russian messages were mainly disseminated through a systematic, coordinated propaganda campaign. Overall, pro-Russian content received ~251,000 retweets and thereby reached around 14.4 million users, primarily in countries such as India, South Africa, and the United States. We further provide evidence that bots played a disproportionate role in the dissemination of propaganda and amplified its proliferation. Overall, 20.28% of the spreaders are classified as bots, most of which were created in the beginning of the invasion. Together, our results highlight the new threats to society that originate from coordinated propaganda campaigns on social media in modern warfare. Our results also suggest that curbing bots may be an effective strategy to mitigate such campaigns

    O Memorial de Imigração Polonesa em Curitiba: dinùmicas culturais e interesses políticos no ùmbito memoralista

    Get PDF
    Neste artigo, analisa-se o conceito de memorial, considerando as atuais definiçÔes de Museu propostas pelo Conselho Internacional de Museus e pelo Instituto Brasileiro de Museus, tendo como objeto de investigação o Memorial de Imigração Polonesa de Curitiba. Evidenciam-se a importĂąncia e a complexidade no trato com o patrimĂŽnio e as dificuldades de pensĂĄ-lo a partir dos sujeitos e das referĂȘncias culturais de determinado grupo em contraponto aos interesses polĂ­ticos e econĂŽmicos; no caso em questĂŁo, voltadas Ă s necessidades da polĂ­tica de city marketing como estratĂ©gia de construção da imagem da cidade. Para tanto, foram considerados os perfis de atuação dos memoriais em diferentes partes do mundo, na tentativa de delimitação conceitual, exemplificando-se a pluralidade de temas e formatos dessas instituiçÔes no Ăąmbito nacional e global. As discussĂ”es levantadas permitem pensar que os Museus Memoriais desempenham as atividades de um memorial no Ăąmbito museolĂłgico, confirmando a ambivalĂȘncia dessas duas instituiçÔes e sua interface privilegiada com o poder polĂ­tico.This article analyzes the memorial concept, considering the Museum definition presented by the International Council of Museums and the Brazilian Institute of Museums. The aim of this study was the Curitiba Polish Immigration Memorial. It highlights the importance and complexity in dealing with the heritage and the difficulties of thinking it from the individuals and the cultural references of certain groups as opposed to political and economic interests; in this case the needs of the city marketing policy as city image building strategy. Therefore, the memorials performance profiles in different parts of the world in an attempt to conceptual definition, exemplifying the diversity of themes and formats of these institutions at the national and global levels. The discussions show that it is possible to consider that the Memorials Museums perform the same activities of a memorial within the museological context, confirming the ambivalence of these two institutions and prime interface with political power

    Pokérator - Unveil your inner Pokémon

    Get PDF
    The Pokérator is a generator of Pokémon names and descriptions, based on user input. The names are generated by blending words based on syllables or characters according to a bigram language model. An accompanying description is generated by filling a template with ConceptNet answers. This sentence is then used as a prompt for text generation with the GPT-2 language model which was finetuned on Pokédex entries. The evaluation of the generated Pokémon names shows that the names are not realistic, but appreciated and creative

    The Transplantation of ω3 PUFA-Altered Gut Microbiota of Fat-1 Mice to Wild-Type Littermates Prevents Obesity and Associated Metabolic Disorders

    No full text
    IF 7.273 (2017)International audienceAltering the gut microbiome may be beneficial to the host, and it recently arose as a promising strategy to manage obesity. Here, we investigated the relative contribution of ω3 polyunsaturated fatty acid (PUFA)-mediated alterations in the microbiota to metabolic parameter changes in mice. Four groups were compared: male fat-1 transgenic mice (with constitutive production of ω3 PUFAs) and male WT littermates fed either an obesogenic (high fat/high sucrose, HFHS) or a control diet. Unlike WT mice, HFHS-fed fat-1 mice were protected against obesity, glucose intolerance and hepatic steatosis. Unlike WT mice, fat-1 mice maintained a normal barrier function, resulting in a significantly lower metabolic endotoxemia. Fat-1 mice displayed greater phylogenic diversity in the cecum, and fecal microbiota transplantation from fat-1 to WT mice was able to reverse weight gain and to normalize glucose tolerance and intestinal permeability. We concluded that the ω3 fatty acid-mediated alteration of gut microbiota contributed to the prevention of metabolic syndrome in fat-1 mice. It occurred independently of changes in PUFA content of host tissues, and may represent a promising strategy to prevent metabolic disease and to preserve a lean phenotype

    Effect of different Ti-6Al-4V surface treatments on osteoblast behaviour

    Get PDF
    The purpose of the present work was to examine the effect of different Ti–6Al–4V surface treatments on osteoblasts behaviour. Previous work in this laboratory has demonstrated that an ageing treatment reduces metal ion release from this alloy compared to standard passivation procedures. In this study, human osteosarcoma MG-63 were used in short-term in vitro tests to assay for cell viability and cell proliferation at 12, 24 and 72 h while SaOS-2 were used in long-term in vitro tests to assay for osteonectin, osteopontin, osteocalcin gene expression, total protein amount (TP), alkaline phosphatase activity (ALP) and fibronectin production (FN) for 1–4 weeks. Epifluorescence microscopy was used to observe SaOS-2 cell morphology. After 24 h, there was no difference in MG-63 cell viability/proliferation or in SaOS-2 cell morphology between the different surface treatments. For the long-term tests, the aged Ti–6Al–4V induced significantly higher cell proliferation than the control Ti–6Al–4V at 72 h. At week 1, no difference in the osteonectin, osteopontin, and osteocalcin gene expression was found between samples. The peak of ALP activity appeared earlier at week 2 for the control surface compared with the passivated and aged surfaces. The early increase in ALP activity for the control sample could be a compensatory effect of decreased osteoblasts proliferation. There was no difference in the expression of FN for the different surface treatments. Our present results showed that the different surface treatments, which induced different metal ion release kinetics and surface properties, influenced the cell proliferation and ALP activity of osteoblast cells. Aluminium ions release kinetics as well as presence of vanadium ions may play a major role in influencing the osteoblasts behaviour in the present study
    corecore