Twitter as a space for interaction in political journalism. Dynamics, consequences and proposal of interactivity scale for social media

This article goes in depth into the key mechanisms that enable a digital interaction between journalists and expert sources in political journalism, developing a scale that articulates these interaction mechanisms on Twitter. On the basis of this analytical proposal, this study tries to reflect the potential professional consequences which are generated by this social network throughout the journalistic work as well as some changes in important professional skills, such as data verification and contact with expert sources. Those are key aspects to determine the opportunities of the journalists in the future of the profession. It also tries to analyse the relationship between journalists and politicians into a digital context by assessing the impact of using different new media tools on the journalistic culture and political discussion

A class of non-supersymmetric orientifolds

We study type IIB orientifolds on T^{2d}/Z_N with supersymmetry broken by the compactification. We determine tadpole cancellation conditions including anti-branes and considering different actions for the parity Omega. Using these conditions we then obtain the spectrum of tachyons and massless states. Various examples with N even correspond to type 0B orientifolds.Comment: 49 pages, Late

Permanent Campaigning: A Meta-Analysis and Framework for Measurement

Permanent campaigning emerged as a concept in the 1970s in studies of US politics but is now recognized as a universal phenomenon. Despite its long history, there has been no attempt to build a holistic picture of the elements that constitute a permanent campaign. Generally, researchers focus on tactical elements, situating their use within an overall strategy, but there is a lack of a broader methodological framework for holistically measuring adherence to the permanent campaigning. This article presents results of a meta-analysis of relevant research to provide a framework to understand how permanent campaigning is practiced. Our study showed there were three reasonably discrete forms of campaigning activities that had been identified: those in which permanent campaign strategies are related to capacity building and strategy; a second, in which permanent campaigning relates to paid and owned media; and a third in which earned media is the main focus. In mapping these studies, we identify the common features of permanent campaigning, identifying strong and weak indicators and the extent these are employed by the government, parties, or elected representatives and within which political systems: parliamentarism or presidentialism. Our framework can be applied in future comparative research to understand trends in political communication

Twitter as a space for interaction in political journalism. Dynamics, consequences and proposal of interactivity scale for social media

This article goes in depth into the key mechanisms that enable a digital interaction between journalists and expert sources in political journalism, developing a scale that articulates these interaction mechanisms on Twitter. On the basis of this analytical proposal, this study tries to reflect the potential professional consequences which are generated by this social network throughout the journalistic work as well as some changes in important professional skills, such as data verification and contact with expert sources. Those are key aspects to determine the opportunities of the journalists in the future of the profession. It also tries to analyse the relationship between journalists and politicians into a digital context by assessing the impact of using different new media tools on the journalistic culture and political discussion

Frequency of the VO2max plateau phenomenon in world-class cyclists

We aimed to determine the frequency of the VO↓2max plateau phenomenon in top-level male professional road cyclists (n = 38; VO↓2max [mean ± SD]: 73.5 ± 5.5 ml · kg↑-1 · min↑-1) and in healthy, sedentary male controls (n = 37; VO↓2max: 42.7 ± 5.6 ml · kg↑-1 · min↑-1). All subjects performed a continuous incremental cycle-ergometer test of 1-min workloads until exhaustion. Power output was increased from a starting value of 25 W (cyclists) or 20 W (controls) at the rate of 25 W · min↑-1(cyclists) or 20 W · min↑-1 (controls) until volitional exhaustion. We measured gas-exchange and heart rate (HR) throughout the test. Blood concentrations of lactate (BLa) were measured at end-exercise in both groups. We defined maximal exercise exertion as the attainment of a respiratory exchange rate (RER) ≥ 1.1; HR > 95 % age-predicted maximum; and BLa> 8 mmo · l↑-1. The VO↓2max plateau phenomenon was defined as an increase in two or more consecutive 1-min mean VO↓2 values of less than 1.5 ml · kg↑-1 · min↑-1. Most cyclists met our criteria for maximal exercise effort (RER > 1.1, 100 %; 95 % predicted maximal HR [HR↓max], 82 %; BLa> 8 mmol · l↑-1, 84 %). However, the proportion of cyclists attaining a VO↓2max plateau was considerably lower, i.e., 47 %. The majority of controls met the criteria for maximal exercise effort (RER > 1.1, 100 %; predicted HR↓max, 68 %; BLa> 8 mmol · l↑-1, 73 %), but the proportion of these subjects with a VO↓2max plateau was only 24 % (significantly lower proportion than in cyclists [p < 0.05]). Scientists should consider 1) if typical criteria of attainment of maximal effort are sufficiently stringent, especially in elite endurance athletes; and 2) whether those humans exhibiting the VO↓2max plateau phenomenon are those who perform an absolute maximum effort or there are additional distinctive features associated with this phenomenon.Sin financiación1.240 JCR (2006) Q2, 31/73 Sport sciencesUE

The miR-424(322)/503 cluster orchestrates remodeling of the epithelium in the involuting mammary gland

The mammary gland is a very dynamic organ that undergoes continuous remodeling. The critical regulators of this process are not fully understood. Here we identify the microRNA cluster miR-424(322)/503 as an important regulator of epithelial involution after pregnancy. Through the generation of a knockout mouse model, we found that regression of the secretory acini of the mammary gland was compromised in the absence of miR-424(322)/503. Mechanistically, we show that miR-424(322)/503 orchestrates cell life and death decisions by targeting BCL-2 and IGF1R (insulin growth factor-1 receptor). Furthermore, we demonstrate that the expression of this microRNA cluster is regulated by TGF-β, a well-characterized regulator of mammary involution. Overall, our data suggest a model in which activation of the TGF-β pathway after weaning induces the transcription of miR-424(322)/503, which in turn down-regulates the expression of key genes. Here, we unveil a previously unknown, multilayered regulation of epithelial tissue remodeling coordinated by the microRNA cluster miR-424(322)/503