The occurrence of planets and other substellar bodies around white dwarfs using K2

The majority of stars both host planetary systems and evolve into a white dwarf (WD). To understand their post-main-sequence (PMS) planetary system evolution, we present a search for transiting/eclipsing planets and other Substellar Bodies (SBs) around WDs using a sample of 1148 WDs observed by K2. Using transit injections, we estimate the completeness of our search. We place constraints on the occurrence of planets and substellar bodies around white dwarfs as a function of planet radius and orbital period. For short-period ($P < 40$ days) small objects, from asteroid-sized to $1.5 \ R_{\oplus}$, these are the strongest constraints known to date. We further constrain the occurrence of hot Jupiters ($< 1.5 \%$), habitable zone Earth-sized planets ($< 28 \%$), and disintegrating short-period planets ($\sim 12 \%$). We blindly recovered all previously known eclipsing objects, providing confidence in our analysis, and make all light curves publicly available.Comment: Accepted by MNRA

Silver as a constraint for a large-scale development of solar photovoltaics? Scenario-making to the year 2050 supported by expert engagement and global sensitivity analysis

In this study we assess whether availability of silver could constrain a large-scale deployment of solar photovoltaics (PV). While silver-paste use in photovoltaics cell metallization is becoming more efficient, solar photovoltaics power capacity installation is growing at an exponential pace. Along photovoltaics, silver is also employed in an array of industrial and non-industrial applications. The trends of these uses are examined up to the year 2050. The technical coefficients for the expansion in photovoltaics power capacity and contraction in silver paste use have been assessed through an expert-consultation process. The trend of use in the non-PV sectors has been estimated through an ARIMA (auto-regressive integrated moving average) model. The yearly and cumulative silver demand are evaluated against the technological potential for increasing silver mining and the estimates of its global natural availability, respectively. The model implemented is tested with a quasi-random Monte Carlo variance-based global sensitivity analysis. The result of our inquiry is that silver may not represent a constraint for a very-large-scale deployment of photovoltaics (up to tens TW in installed power capacity) provided the present decreasing trend in the use of silver paste in the photovoltaics sector continues at an adequate pace. Silver use in non-photovoltaic sectors plays also a tangible influence on potential constraints. In terms of natural constraints, most of the uncertainty is dependent on the actual estimates of silver natural budget

Key findings from the 2006 Scottish Health Behaviour in School-aged Children study

The HBSC study in Scotland is funded by NHS Health Scotland.Publisher PD

Network neutrality between false positives and false negatives:Introducing a European approach to American broadband markets

Network neutrality has become a contentious issue both in Europe and the United States. Regulators on both sides of the Atlantic face digital divides in their society, and are confronted with potentially conflicting policy goals-to incentivize private investment in next-generation broadband while maintaining neutral and competitive broadband networks. This Article compares nascent American and European network neutrality policy in terms of regulatory error costs. Emerging markets, such as broadband, are more likely to be affected by regulatory errors, and these errors have graver consequences in emerging markets than in regular markets. U.S. telecommunications policy traditionally has advanced a trial-and-error approach of categorical intervention against specific regulatory errors. However, analysis shows that categorical regulation misrepresents the complexity of network neutrality and emerging broadband markets. European policy, on the other hand, may have the potential to employ a dynamic regulatory mechanism that allows for targeting more regulatory errors at once; however, it fails to live up to this promise with network neutrality. Therefore, this Article recommends that U.S. policymakers develop an analytic and dynamic regulatory model for network neutrality, which builds on European precedent yet learns from European regulatory mistakes. A practical reform scenario suggests that such a model is best implemented by the FCC, which has the opportunity to draft a comprehensive national broadband plan under the Recovery Act. With regard to its national broadband plan, the FCC should position itself to monitor broadband markets and deal with network neutrality in a flexible and transparent manner

Recalibrating the compass: towards effective competition law enforcement on mixed markets

The undertaking, a cornerstone of EU competition law, has consistently been approached as a functional concept. Any entity engaged in economic activity should be considered an undertaking, thereby ensuring consistent application of competition law across competitors. However, current national enforcement practice reveals a departure from the functional approach to the undertaking on mixed markets, where public and private firms compete. Particularly, allegedly anticompetitive behaviour by public entities has evaded competition law scrutiny in the Netherlands, because competition law was found not to apply to these public entities. Drawing on a jointly interpreted string of CJEU cases in competition law and state aid law – which this article coins as the “Compass doctrine” – the Dutch competition authority and courts found that economic activity by public entities is exempt from competition law when connected to the exercise of public power. Analysis of the Compass doctrine cases reveals how a number of case-specific outcomes taken together have allowed for an undermining of the functional approach to the undertaking. It is demonstrated how the sum of the Compass doctrine is larger than its individual parts, which seems to have been unforeseen by the CJEU. This article demonstrates how the Compass doctrine has two adverse consequences: (1) because it undermines the functional approach to the undertaking as the subject of competition law, it impedes effective enforcement; (2) the Compass doctrine enables public firms to behave anticompetitively on mixed markets. The CJEU never anticipated the advent of commercial behaviour by public entities, who with the Compass doctrine in hand can infringe competition law with impunity. Experiences in the Netherlands to this effect should be regarded as a canary in the coal mine for mixed markets across the EU. Therefore, it is incumbent on the CJEU to revisit the Compass doctrine in future cases, which may follow from preliminary references. This article recommends the CJEU to (re)emphasize that once an entity is engaged in economic activity, it can no longer escape competition law scrutiny by being connected to the exercise of public authority. To protect the level playing field on mixed markets, all economic activity should explicitly be subject to EU competition law