Microwaves (MWs) have emerged as a promising sensing technology to complement optical methods for monitoring floating plastic litter. This study uses machine learning (ML) to identify optimal MW frequencies for detecting floating macroplastics (>5 cm) across S, C, and X-bands. Data were obtained from dedicated wideband backscattering radio measurements conducted in a controlled indoor scenario that mimics deep-sea conditions. The paper presents new strategies to directly analyze the frequency domain signals using ML algorithms, instead of generating an image from those signals and analyzing the image. We propose two ML workflows, one unsupervised, to characterize the difference in feature importance across the measured MW spectrum, and the other supervised, based on multilayer perceptron, to study the detection accuracy in unseen data. For the tested conditions, the backscatter response of the plastic litter is optimal at X-band frequencies, achieving accuracies up to 90% and 80% for lower and higher water wave heights, respectively. Multiclass classification is also investigated to distinguish between different types of plastic targets. ML results are interpreted in terms of the physical phenomena obtained through numerical analysis, and quantified through an energy-based metric.

The so-called credibility revolution dominates empirical economics, with its promise of causal identification to improve scientific knowledge and ultimately policy. By examining the case of rural electrification in the Global South, this opinion paper exposes the limits of this evidence-based policy paradigm. The electrification literature boasts many studies using the credibility revolution toolkit, but at the same time, several systematic reviews demonstrate that the evidence is divided between very positive and muted effects. This bifurcation presents a challenge to the science-policy interface, where policymakers, lacking the resources to sift through the evidence, may be drawn to the results that serve their (agency's) interests. The interpretation is furthermore complicated by unresolved methodological debates circling around external validity as well as selective reporting and publication decisions. These features, we argue, are not particular to the electrification literature but inherent to the credibility revolution toolkit.

The influence of Cu(II) on the hydrothermal and thermal transformations of a synthetic hectorite was investigated by a combined approach using mainly X-ray diffraction, thermal analyses, and electron paramagnetic resonance spectroscopy. The presence of Cu(II) during hydrothermal treatment increased the crystallite size. Copper (II) was both structure-bound and associated with the inner surfaces of the particles. Upon heating, structural destabilization of the hectorite began at ∼400°C as indicated by the formation of free radicals. Between 600 and 700°C, the hectorite converted to enstatite, and in the presence of Cu(II), to enstatite and richterite. The formation of richterite as an additional conversion product is explained by the creation of structural weakness due to structure-bound Cu(II) in F-containing hectorite. Our results suggest that traces of Cu(II), typical of natural environments, may influence the conversion products in high-temperature geochemical systems.

The Centre for Advanced Laser Applications in Garching, Germany, is home to the ATLAS-3000 multi-petawatt laser, dedicated to research on laser particle acceleration and its applications. A control system based on Tango Controls is implemented for both the laser and four experimental areas. The device server approach features high modularity, which, in addition to the hardware control, enables a quick extension of the system and allows for automated data acquisition of the laser parameters and experimental data for each laser shot. In this paper we present an overview of our implementation of the control system, as well as our advances in terms of experimental operation, online supervision and data processing. We also give an outlook on advanced experimental supervision and online data evaluation – where the data can be processed in a pipeline – which is being developed on the basis of this infrastructure.

Understanding the transfer of polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) as well as polychlorinated biphenyls (PCBs) from oral exposure into cow’s milk is not purely an experimental endeavour, as it has produced a large corpus of theoretical work. This work consists of a variety of predictive toxicokinetic models in the realms of health and environmental risk assessment and risk management. Their purpose is to provide mathematical predictive tools to organise and integrate knowledge on the absorption, distribution, metabolism and excretion processes. Toxicokinetic models are based on more than 50 years of transfer studies summarised in part I of this review series. Here in part II, several of these models are described and systematically classified with a focus on their applicability to risk analysis as well as their limitations. This part of the review highlights the opportunities and challenges along the way towards accurate, congener-specific predictive models applicable to changing animal breeds and husbandry conditions.

Polychlorinated dibenzo-para-dioxins (PCDDs) and dibenzofurans (PCDFs) (collectively and colloquially referred to as ‘dioxins’) as well as polychlorinated biphenyls (PCBs) are persistent and ubiquitous environmental contaminants that may unintentionally enter and accumulate along the food chain. Owing to their chronic toxic effects in humans and bioaccumulative properties, their presence in feed and food requires particular attention. One important exposure pathway for consumers is consumption of milk and dairy products. Their transfer from feed to milk has been studied for the past 50 years to quantify the uptake and elimination kinetics. We extracted transfer parameters (transfer rate, transfer factor, biotransfer factor and elimination half-lives) in a machine-readable format from seventy-six primary and twenty-nine secondary literature items. Kinetic data for some toxicologically relevant dioxin congeners and the elimination half-lives of dioxin-like PCBs are still not available. A well-defined selection of transfer parameters from literature was statistically analysed and shown to display high variability. To understand this variability, we discuss the data with an emphasis on influencing factors, such as experimental conditions, cow performance parameters and metabolic state. While no universal interpretation could be derived, a tendency for increased transfer into milk is apparently connected to an increase in milk yield and milk fat yield as well as during times of body fat mobilisation, for example during the negative energy balance after calving. Over the past decades, milk yield has increased to over 40 kg/d during high lactation, so more research is needed on how this impacts feed to food transfer for PCDD/Fs and PCBs.

Ordering is a well-established concept in mathematics and also plays an important role in many areas of computer science, where quasi-orderings, most notably well-founded quasi-orderings and well-quasi-orderings, are of particular interest. This paper deals with quasi-orderings on first-order terms and introduces a new notion of unification based on a special quasi-order, known as homeomorphic tree embedding. Historically, the development of unification theory began with the central notion of a most general unifier based on the subsumption order. A unifier $\sigma$ is most general, if it subsumes any other unifier $\tau$, that is, if there is a substitution $\lambda$ with $\tau=_{E}\sigma\lambda$, where E is an equational theory and $=_{E}$ denotes equality under E. Since there is in general more than one most general unifier for unification problems under equational theories E, called E-Unification, we have the notion of a complete and minimal set of unifiers under E for a unification problem $\varGamma$, denoted as $\mu\mathcal{U}\Sigma_{E}(\Gamma)$. This set is still the basic notion in unification theory today. But, unfortunately, the subsumption quasi-order is not a well-founded quasi-order, which is the reason why for certain equational theories there are solvable E-unification problems, but the set $\mu\mathcal{U}\Sigma_{E}(\Gamma)$ does not exist. They are called type nullary in the unification hierarchy. In order to overcome this problem and also to substantially reduce the number of most general unifiers, we extended the well-known encompassment order on terms to an encompassment order on substitutions (modulo E). Unification under the encompassment order is called essential unification and if $\mu\mathcal{U}\Sigma_{E}(\Gamma)$ exists, then the complete set of essential unifiers $e\mathcal{U}\Sigma_{E}(\Gamma)$ is a subset of $\mu\mathcal{U}\Sigma_{E}(\Gamma)$. An interesting effect is that many E-unification problems with an infinite set of most general unifiers (under the subsumption order) reduce to a problem with only finitely many essential unifiers. Moreover, there are cases of an equational theory E, for which the complete set of most general unifiers does not exist, the minimal and complete set of essential unifiers however does exist. Unfortunately again, the encompassment order is not a well-founded quasi-ordering either, that is, there are still theories with a solvable unification problem, for which a minimal and complete set of essential unifiers does not exist. This paper deals with a third approach, namely the extension of the well-known homeomorphic embedding of terms to a homeomorphic embedding of substitutions (modulo E). We examine the set of most general, minimal, and complete E-unifiers under the quasi-order of homeomorphic embedment modulo an equational theory E, called $\varphi U\Sigma_{E}(\Gamma)$, and propose an appropriate definitional framework based on the standard notions of unification theory extended by notions for the tree embedding theorem or Kruskal’s theorem as it is called. The main results are that for regular theories the minimal and complete set $\varphi\mathcal{U}\Sigma_{E}(\Gamma)$ always exists. If we restrict the E-embedding order to pure E-embedding, a well-known technique in logic programming and term rewriting where the difference between variables is ignored, the set $\varphi_{\pi}\mathcal{U}\Sigma_{E}(\Gamma)$ always exists and it is even finite for any theory E.

This paper studies the role of monetary policy for the dynamics of US mortgage debt, which accounts for the largest part of household debt. A time-varying parameter vector autoregressive (VAR) model allows us to study the variation in the sensitivity of mortgage debt to monetary policy. We find that an identically sized policy shock became less effective over time. We use a dynamic stochastic general equilibrium model to show that a fall in the share of adjustable rate mortgages (ARMs) can replicate this finding. Calibrating the model to the drop in the ARM share since the 1980s yields a decline in the sensitivity of housing debt to monetary policy which is quantitatively similar to the VAR results. A sacrifice ratio for mortgage debt reveals that a policy tightening directed toward reducing household debt became more expensive in terms of a loss in employment. Counterfactuals show that this result cannot be attributed to changes in monetary policy itself.

In a ruling on 25 July 2018, the Court of Justice of the European Union concluded that organisms obtained by means of techniques/methods of mutagenesis constitute GMOs in the sense of Directive 2001/18, and that organisms obtained by means of techniques/methods of directed mutagenesis are not excluded from the scope of the Directive. Following the ruling, there has been much debate about the possible wider implications of the ruling. In October 2019, the Council of the European Union requested the European Commission to submit, in light of the CJEU ruling, a study regarding the status of novel genomic techniques under Union Law. For the purpose of the study, the Commission initiated stakeholder consultations early in 2020. Those consultations focused on the technical status of novel genomic techniques.

This article aims to contribute to the discussion on the legal status of organisms developed through novel genomic techniques, by offering some historical background to the negotiations on the European Union (EU) GMO Directives as well as a technical context to some of the terms in the Directive, and by analysing the ruling. The article advances that (i) the conclusion that organisms obtained by means of techniques/methods of mutagenesis constitute GMOs under the Directive means that the resulting organisms must comply with the GMO definition, ie the genetic material of the resulting organisms has been altered in a way that does not occur naturally by mating and/or natural recombination; (ii) the conclusion that organisms obtained by means of techniques/methods of directed mutagenesis were not intended to be excluded from the scope of the Directive is not inconsistent with the negotiation history of the Directive; (iii) whether an organism falls under the description of “obtained by means of techniques/methods of directed mutagenesis” depends on whether the genetic material of the resulting organisms has been altered in a way that does not occur naturally by mating and/or natural recombination. Finally, the article offers an analysis of the EU GMO definition, concluding that for an organism to be a GMO in the sense of the Directive, the technique used, as well as the genetic alterations of the resulting organism, must be considered.

The original description of the large and characteristic belemnite species Arctoteuthis bluethgeni Doyle was based on fragmentary material from a relatively uncertain stratigraphic interval in Kong Karls Land, Svalbard. Recent collection of a belemnite assemblage in the Lower Cretaceous Rurikfjellet Formation on Spitsbergen include numerous complete specimens, allowing a detailed description of the species. With the exception of a specimen reported from Arctic Canada, its distribution is restricted to Svalbard. Its stratigraphic range appears to be restricted to the upper Valanginian – lower Hauterivian from ages obtained from palynostratigraphy. A. bluethgeni is therefore considered to be a useful Lower Cretaceous guide fossil in the Boreal High Arctic.

Köhnlein (2016) proposes to represent the Franconian tone contrast as a difference in foot structure, whereby Accent 1 appears in lexically marked syllabic trochees and Accent 2 in default moraic trochees, as an alternative to analyses with an underlying privative tone for Accent 2. After sketching the two approaches, we argue against three arguments Köhnlein advances in favour of the metrical analysis. We then show that one of the disadvantages incurred by the metrically derived tonal representations is the introduction of a novel and otherwise unsupported concept of a single tone that incorporates two morphologically different but phonologically identical tones. We also evaluate Köhnlein's (2018) more recent proposal to use the syllabic trochee to account for subtractive plurals in tonal dialects. Finally, we compare the predictive powers of the metrical and tonal analyses of the Arzbach dialect.

The societal mega-trends of the past four decades, such as a globalizing economy and an aging society, have challenged the understanding of the state in OECD countries. The resulting “transformations of the state” are the subject of an interdisciplinary research agenda established at the Collaborative Research Center (CRC) 597 in Bremen, Germany. A total of twenty projects from political science, law, and economics explore changes of statehood which take place in two different dimensions: first, the internationalization and, second, the privatization of activities and functions which were traditionally performed by and ascribed to the democratic, constitutional and interventionist state. While the first research phase (2003-2006) aimed at founding empirical descriptions of these internationalization and privatization processes, the current phase (2007-2010) is dedicated to explaining the observed changes in statehood. Within this general framework, the authors’ research project on “New Forms of Legal Certainty in Globalized Exchange Processes” deals with changes in the institutional organization of commerce.

This research aims to explore the submerged landscapes of the Pilbara of western Australia, using predictive archaeological modelling, airborne LiDAR, marine acoustics, coring and diver survey. It includes excavation and geophysical investigation of a submerged shell midden in Denmark to establish guidelines for the underwater discovery of such sites elsewhere.

Two-or three-dimensional avalanche-simulation models offer a wide range of applications; however, a challenging model-verification process is demanded, accompanied by a reliable determination of model-input parameters. We show that a verification process can be arranged with remote-monitoring data from an artificially triggered avalanche, leading to the calculation of avalanche mass balance. Two numerical methods are applied to increase the quality of the parameter fit and to reduce the number of simulations. The quality of the parameter fit is verified by comparing measured and simulated run-out lengths. In addition, a cross-check is performed using velocities derived from Doppler radar measurements.