Social features of online networks: the strength of intermediary ties in online social media

An increasing fraction of today social interactions occur using online social media as communication channels. Recent worldwide events, such as social movements in Spain or revolts in the Middle East, highlight their capacity to boost people coordination. Online networks display in general a rich internal structure where users can choose among different types and intensity of interactions. Despite of this, there are still open questions regarding the social value of online interactions. For example, the existence of users with millions of online friends sheds doubts on the relevance of these relations. In this work, we focus on Twitter, one of the most popular online social networks, and find that the network formed by the basic type of connections is organized in groups. The activity of the users conforms to the landscape determined by such groups. Furthermore, Twitter's distinction between different types of interactions allows us to establish a parallelism between online and offline social networks: personal interactions are more likely to occur on internal links to the groups (the weakness of strong ties), events transmitting new information go preferentially through links connecting different groups (the strength of weak ties) or even more through links connecting to users belonging to several groups that act as brokers (the strength of intermediary ties).Comment: 14 pages, 18 figure

How social media can afford engagement processes

The increasing popularity of social media has led many organizations to find new ways of customer engagement. This paper presents an initial pilot study to explore the affordance of social media in engagement processes. By applying the affordance theory and Porter’s process for engagement model, we used a case study approach to examine the case company’s Facebook and Twitter content to identify the engagement possibilities of social media. Our preliminary results show that social media opens a new channel for organisations to engage with their customers. We present a preliminary theoretical model to understand the how the functional affordances of social media are socialised in engagement processes, which ultimately gives rise to socialised affordances

Efeitos da terapia ultrassônica de baixa intensidade sobre o infarto agudo do miocárdio em ratos

Introdução. O infarto agudo do miocárdio (IAM) é considerado importante causa de morbidade e mortalidade no mundo e no Brasil. Novas intervenções terapêuticas estão sendo testadas isoladas ou em associação com as já existentes com o intuito de impedir a progressão ou atenuar o remodelamento no coração infartado. Dentre elas destaca-se a aplicação do Ultra-som (US) conjunto com agentes trombolíticos. Entretanto, na aplicação da energia ultrassônica como terapêutica pós-infarto é avaliado somente o seu possível efeito como agente trombolítico, não sendo investigado a sua possível implicação no processo de cicatrização da área infartada e parâmetros funcionais cardíacos. Objetivos. Diante dessas informações, nós objetivamos avaliar os efeitos da terapia ultrassônica transtorácica não-invasiva de baixa intensidade (NITUS) sobre a morfologia e função do músculo cardíaco de ratos infartados cirurgicamente após o 5° e 30° dia. Metodologia. Ratos machos Wistar (200-250g) foram pesados e divididos aleatoriamente em oito grupos com oito animais em cada grupo. Quatro grupos de animais foram submetidos à indução do IAM através da oclusão permanente da artéria coronária descendente anterior esquerda, sendo que dois destes grupos foram sacrificados no 5° dia após o IAM e as cinco aplicações da terapia ultrassônica e os outros dois grupos foram sacrificados no 30° dia após o IAM e as 5 aplicações da terapia ultrassônica. Quatro grupos de animais foram submetidos à cirurgia fictícia (Sham), sendo que dois destes grupos foram sacrificados no 5° dia após a cirurgia fictícia e as 5 aplicações da terapia ultrassônica e os outros dois grupos foram sacrificados no 30° dia após a cirurgia fictícia e as 5 aplicações da terapia ultrassônica. Os parâmetros da terapia ultrassônica foram freqüência de 1MHz, potência de 1W/cm2, modo pulsado e tempo de aplicação de 5 minutos. Para avaliação dos parâmetros funcionais foi realizado registros hemodinâmicos de todos os grupos e após a coleta dos registros os corações foram retirados para análise morfométrica a fim de avaliar a área da cicatriz do infarto. Os corações foram cortados em 4 fatias sendo retirados 3 cortes com espessura de 8 micrômetros da terceira fatia do ápice para a base, e estes foram corados com picrosírius. Foi utilizada uma câmera de vídeo para capturar uma área que contivesse todo o corte. A imagem era capturada com a utilização do programa AMCap e após a captura, esta era arquivada. A imagem arquivada era transferida para o programa ImageJ 1.42q/java no qual era marcada a área da cicatriz. De modo semelhante, era marcada toda a área da parede ventricular, para se obter a relação entre a área da cicatriz e a área total da parede ventricular. Resultados. No que concerne aos parâmetros hemodinâmicos, observamos que 30 dias após o IAM houve redução na pressão diastólica final (PDF) (mmHg) do grupo IAM+US quando comparado com grupo IAM (15±1.9 e 26±1.4; p<0.01 respectivamente). Não houve diferença significativa na área da cicatriz do infarto entre os grupos IAM e IAM+US no 5º. dia após infarto (31.6%±3.1% e 34.5%±1.6, respectivamente). Houve redução da área da cicatriz do infarto no grupo IAM+US quando comparado ao grupo IAM (21.5%±1.4% e 26.2%±1.7%; p<0.05, respectivamente) no 30º dia após IAM. Conclusão. A terapia com US dentro dos parâmetros estabelecidos, reduziu a área da cicatriz do infarto no grupo IAM+US (30 dias) bem como manteve a PDF dentro de valores fisiológicos, provavelmente por exercer influência nas fases inflamatória, proliferativa e de remodelamento, o que favorece um aumento na velocidade da resposta inflamatória por meio da mobilização de células inflamatórias como neutrófilos, macrófagos, ao mesmo tempo em que estimulou à degranulação dos mastócitos, bem como interferiu na mobilização leucocitária

Crowdsourcing: A new tool for policy-making?

Crowdsourcing is rapidly evolving and applied in situations where ideas, labour, opinion or expertise of large groups of people are used. Crowdsourcing is now used in various policy-making initiatives; however, this use has usually focused on open collaboration platforms and specific stages of the policy process, such as agenda-setting and policy evaluations. Other forms of crowdsourcing have been neglected in policy-making, with a few exceptions. This article examines crowdsourcing as a tool for policy-making, and explores the nuances of the technology and its use and implications for different stages of the policy process. The article addresses questions surrounding the role of crowdsourcing and whether it can be considered as a policy tool or as a technological enabler and investigates the current trends and future directions of crowdsourcing. Keywords: Crowdsourcing, Public Policy, Policy Instrument, Policy Tool, Policy Process, Policy Cycle, Open Collaboration, Virtual Labour Markets, Tournaments, Competition

Webometrics benefitting from web mining? An investigation of methods and applications of two research fields

Webometrics and web mining are two fields where research is focused on quantitative analyses of the web. This literature review outlines definitions of the fields, and then focuses on their methods and applications. It also discusses the potential of closer contact and collaboration between them. A key difference between the fields is that webometrics has focused on exploratory studies, whereas web mining has been dominated by studies focusing on development of methods and algorithms. Differences in type of data can also be seen, with webometrics more focused on analyses of the structure of the web and web mining more focused on web content and usage, even though both fields have been embracing the possibilities of user generated content. It is concluded that research problems where big data is needed can benefit from collaboration between webometricians, with their tradition of exploratory studies, and web miners, with their tradition of developing methods and algorithms

I Click, Therefore I am:Predicting Clicktivist-Like Actions on Candidates’ Facebook Posts During the 2016 US Primary Election

Facebook “likes” are often used as a proxy of users’ attention and an affirmation of what is posted on Facebook (Gerodimos &amp; Justinussen, 2015). To determine what factors predict “likes,” the authors analyzed Facebook posts made by the campaigns of Hillary Clinton, Bernie Sanders, and Donald Trump, the top three candidates from the 2016 US primary election. Several possible factors were considered, such as the types of posts, the use of pronouns and emotions, the inclusion of slogans and hashtags, references made to opponents, as well as candidate’s mentions on national television. The results of an ordinary least-squared regression analysis showed that the use of highly charged (positive or negative) emotions and personalized posts (first-person singular pronouns) increased “likes” across all three candidates’ Facebook pages, whereas visual posts (posts containing either videos or photos) and the use of past tenses were liked more often by Hillary Clinton and Bernie Sanders’ followers than by Trump’s followers. Television mentions boosted likes on Clinton and Sanders’ posts but had a negative effect on Trump’s. The study contributes to the growing literature on digitally networked participation (Theocharis, 2015) and supports the emerging notion of the new “hybrid media” system (Chadwick, 2013) for political communication. The study also raises questions as to the relevance of platforms such as Facebook to deliberative democratic processes since Facebook users are not necessarily engaging with the content in an organic way, but instead might be guided to specific content by the Facebook timeline algorithm and targeted ads