Active galactic nuclei (AGN) have been observed as far as redshift. They are crucial in investigating the early Universe as well as the growth of supermassive black holes at their centres. Radio-loud AGN with their jets seen at a small viewing angle are called blazars and show relativistic boosting of their emission. Thus, their apparently brighter jets are easier to detect in the high-redshift Universe. DES J014132.4-542749.9 is a radio-luminous but X-ray weak blazar candidate at. We conducted high-resolution radio interferometric observations of this source with the Australian Long Baseline Array at and GHz. A single, compact radio-emitting feature was detected at both frequencies with a flat radio spectrum. We derived the milliarcsecond-level accurate position of the object. The frequency dependence of its brightness temperature is similar to that of blazar sources observed at lower redshifts. Based on our observations, we can confirm its blazar nature. We compared its radio properties with those of two other similarly X-ray-weak and radio-bright AGN, and found that they show very different relativistic boosting characteristics.

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Regulatory regimes designed to ensure transparency often struggle to ensure that transparency is meaningful in practice. This challenge is particularly great when coupled with the widespread usage of dark patterns - design techniques used to manipulate users. The following article analyses the implementation of the transparency provisions of the German Network Enforcement Act (NetzDG) by Facebook and Twitter, as well as the consequences of these implementations for the effective regulation of online platforms. This question of effective regulation is particularly salient, due to an enforcement action in 2019 by Germany's Federal Office of Justice (BfJ) against Facebook for what the BfJ claim were insufficient compliance with transparency requirements, under NetzDG. This article provides an overview of the transparency requirements of NetzDG and contrasts these with the transparency requirements of other relevant regulations. It will then discuss how transparency concerns not only providing data, but also how the visibility of the data that is made transparent is managed, by deciding how the data is provided and is framed. We will then provide an empirical analysis of the design choices made by Facebook and Twitter, to assess the ways in which their implementations differ. The consequences of these two divergent implementations on interface design and user behaviour are then discussed, through a comparison of the transparency reports and reporting mechanisms used by Facebook and Twitter. As a next step, we will discuss the BfJ's consideration of the design of Facebook's content reporting mechanisms, and what this reveals about their respective interpretations of NetzDG's scope. Finally, in recognising that this situation is one in which a regulator is considering design as part of their action - we develop a wider argument on the potential for regulatory enforcement around dark patterns, and design practices more generally, for which this case is an early, indicative example.@en

Volonteri et al. (2011) found that the number of radio-loud quasars above redshift 4 calculated from the luminosity function (based upon Swift/BAT observations) is much smaller than the number estimated from the known high-redshift beamed sources, blazars, assuming that for every beamed source with a Lorentz factor of Γ, statistically 2Γ² non-beamed sources should exist. To explain the missing misaligned (non-beamed) population of high-redshift sources, they proposed various explanations, involving heavy optical obscuration and significantly different Lorentz factors at early cosmological epochs. Our EVN observations targeting high-redshift (z > 4) blazar candidates revealed 3 sources not showing relativistic beaming, but rather kpc-scale double structures. These three sources have significant radio emission resolved out with the EVN, while they are compact on ~ 5 − 10 arcsec scale. Our dual-frequency (1.5 and 5 GHz) e-MERLIN observations of these three sources revealed a rich morphology, bending jets, and hot spots with possible sites of interaction between the jets and the surrounding medium at intermediate scales.

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