High-accuracy experimental determination of photon mass attenuation coefficients of transition metals and lithium fluoride in the ultra-soft energy range.

In the field of quantitative X-ray analysis techniques, such as electron probe microanalysis, precise knowledge of fundamental parameters is crucial. Especially, the accurate determination of photon mass attenuation coefficients is essential to perform correct elemental quantification. While the widely used databases offer agreement for the hard X-ray range, significant differences arise for lower photon energies. Furthermore, addressing the uncertainties of the tabulated data, which can be of several hundreds of percent, is of urgent need. Driven by recent advances in analytical techniques in the low energy range including investigation of materials containing lithium, the interest in a reliable set of photon mass attenuation coefficients is steadily increasing. In this study, we experimentally determine photon mass attenuation coefficients for lithium fluoride, aluminium, and different transition metals in the extreme low energy range from 40 eV to a several hundreds of eV. This high-precision experimental determination allows a comparison with the existing data tables. We observe differences that turn out to be significant, especially around the absorption edges.

Modernizing persistence-bioaccumulation-toxicity (PBT) assessment with high throughput animal-free methods.

The assessment of persistence (P), bioaccumulation (B), and toxicity (T) of a chemical is a crucial first step at ensuring chemical safety and is a cornerstone of the European Union's chemicals regulation REACH (Registration, Evaluation, Authorization, and Restriction of Chemicals). Existing methods for PBT assessment are overly complex and cumbersome, have produced incorrect conclusions, and rely heavily on animal-intensive testing. We explore how new-approach methodologies (NAMs) can overcome the limitations of current PBT assessment. We propose two innovative hazard indicators, termed cumulative toxicity equivalents (CTE) and persistent toxicity equivalents (PTE). Together they are intended to replace existing PBT indicators and can also accommodate the emerging concept of PMT (where M stands for mobility). The proposed "toxicity equivalents" can be measured with high throughput in vitro bioassays. CTE refers to the toxic effects measured directly in any given sample, including single chemicals, substitution products, or mixtures. PTE is the equivalent measure of cumulative toxicity equivalents measured after simulated environmental degradation of the sample. With an appropriate panel of animal-free or alternative in vitro bioassays, CTE and PTE comprise key environmental and human health hazard indicators. CTE and PTE do not require analytical identification of transformation products and mixture components but instead prompt two key questions: is the chemical or mixture toxic, and is this toxicity persistent or can it be attenuated by environmental degradation? Taken together, the proposed hazard indicators CTE and PTE have the potential to integrate P, B/M and T assessment into one high-throughput experimental workflow that sidesteps the need for analytical measurements and will support the Chemicals Strategy for Sustainability of the European Union.

Social Perception of Systemic Risks.

The article distinguishes between two types of risks: conventional and systemic risks. Conventional risks can be contained in space and time, follow linear cause-effect relationships and can be addressed with effective and pointed interventions into the cause-effect chain. Systemic risks, however, are characterized by high complexity, transboundary effects, stochastic relationships, nonlinear cause-effect patterns with tipping points, and are often associated with less public attention than they require. The article addresses the reasons why systemic risks seem to be attenuated in public perception. The article goes on to consider how the social amplification of risk framework is useful in the context of systemic risks and describes needed extensions of that framework. It identifies practical tools for assessing the significance of perceptions for systemic risk situations. Finally, it argues that a graphic representation and simulation of evolving systemic risks and potential countermeasures as well as a participatory deliberative approach of inclusive risk governance are suitable governance strategies for preventing, mitigating, or managing systemic risks.

Risk Researchers' Views About the Goal of Trying to Ensure Policymakers Consider Scientific Evidence.

A survey of members of a scientific society focused on risk analysis suggests substantial support for seeing their scientific society pursue the communication goal of "trying to ensure that policymakers consider scientific evidence." Support for pursuing this goal was largely predicted by researchers' beliefs that it was ethical for the society to pursue the goal, that it would be satisfying to see their society pursue the goal, and the belief that the society could have a positive impact on society by pursuing the goal. Normative beliefs about pursuing the goal and organizational efficacy beliefs were not good predictors of goal support. Goal support was measured using a direct measure of perceived goal importance as well as measures focused on the degree to which respondents wanted their society to put resources into providing members with opportunities to pursue the goal and the amount of funding that members thought the society should devote to pursuing the goal. The theory underlying the work argues that we can treat science communicators' choices about communication goals, objectives, and tactics as "planned behaviors" and thus study them using traditional behavior change models.

Systemic Risks from Different Perspectives.

Systemic risks are characterized by high complexity, multiple uncertainties, major ambiguities, and transgressive effects on other systems outside of the system of origin. Due to these characteristics, systemic risks are overextending established risk management and create new, unsolved challenges for policymaking in risk assessment and risk governance. Their negative effects are often pervasive, impacting fields beyond the obvious primary areas of harm. This article addresses these challenges of systemic risks from different disciplinary and sectorial perspectives. It highlights the special contributions of these perspectives and approaches and provides a synthesis for an interdisciplinary understanding of systemic risks and effective governance. The main argument is that understanding systemic risks and providing good governance advice relies on an approach that integrates novel modeling tools from complexity sciences with empirical data from observations, experiments, or simulations and evidence-based insights about social and cultural response patterns revealed by quantitative (e.g., surveys) or qualitative (e.g., participatory appraisals) investigations. Systemic risks cannot be easily characterized by single numerical estimations but can be assessed by using multiple indicators and including several dynamic gradients that can be aggregated into diverse but coherent scenarios. Lastly, governance of systemic risks requires interdisciplinary and cross-sectoral cooperation, a close monitoring system, and the engagement of scientists, regulators, and stakeholders to be effective as well as socially acceptable.

[Theories of stages of life within the anthropology of romanticism]. / Lebensaltertheorien in der Anthropologie der Romantik.

The essay discusses the importance and prominence of theories about different stages of life in the anthropological and medical discourse of romanticism. This discourse has clearly a stabilising and restaurative function, favouring the age of moderate manhood. The political and social regulative implications of these theories demand a restaurative roll-back. The essay is based on a concept of sociology of knowledge formation.