Ramboll (Germany)

We appreciate the opportunity to comment on the case report ‘Asbestosis Requiring Lung Transplantation in a Retired Hairdresser: An Occupational Exposure to Comb Through’ authored by Bu et al. [1] The authors report a case that they concluded was asbestosis in a retired hairdresser and speculate the source of asbestos exposure was the use of hair dryers containing asbestos, along with the possible contamination of cosmetic talc with asbestos. Asbestosis in hairdresser cohorts would be a novel finding, but as we discuss below, several lines of reasoning from the scientific literature raise serious questions as to the conclusions in this case report. Alternative explanations should be further pursued. Asbestosis is a marker of relatively high asbestos exposure. Clinical findings of asbestosis have been reported at 25 fibre-years/cm3 (f-yrs/cc) or higher [2], with exposures at the current Occupational Safety and Health Administration permissible exposure limit and American Conference of Governmental Industrial Hygienists threshold limit value of 0.1 f/cc for a career (i.e., 4 or 4.5 f-yrs/cc) protective of asbestosis risk. Hair dryers may have historically contained a non-friable chrysotile asbestos component. Exposures related to the use of hair dryers show relatively low task-based exposure; the authors reference a 1979 report from the National Institute for Occupational Safety and Health that showed ‘structures’ between zero and 0.11 structures/cc (s/cc). Asbestos exposures reported in s/cc are not a reliable means of ascertaining asbestos-related disease risk, and ‘fibres’ longer than 5 μm (μm) are a minimum cutoff in asbestos regulatory definitions. Nonetheless, using conservative assumptions, cumulative airborne exposures for a career hairdresser would be far below 4 f-yrs/cc. The authors presented an erroneous calculation of cumulative yearly exposure of ‘25,100 fibres per cubic centimetre each year’, when the actual reference in Roggli et al. is in the range of ‘25 to 100 fibres/mL-years’ (e.g., f-yrs/cc) [2]. Additionally, it is not appropriate to assume that s/cc is directly comparable to f/cc. When placed in the correct context, the authors' suggestion that the use of hair dryers poses a risk of asbestosis is not supported. Additionally, the possible presence of asbestos in cosmetic talc since the 1970s has been demonstrated to result in diminishingly low exposures [3], which is confirmed by the lack of mesothelioma risk in hairdressers [4]. The literature simply does not support any likelihood of asbestosis risk from the use of cosmetic talc. The authors reportedly found asbestos bodies in the lung. Further information would elucidate this finding, including whether the asbestos body count is greater than background levels and the fibre type identified. For example, an asbestos body composed of a commercial amphibole asbestos would rule out the asbestos exposures reported and discussed above, and may suggest other unidentified exposures if the asbestosis diagnosis is validated. Case reports are appropriate for generating hypotheses but are insufficient for drawing the sweeping conclusions that the authors are attempting to make. Readers are cautioned against drawing any conclusive inferences with the available information in the etiological determination of a purported asbestosis case. Evan Anderson drafted the letter. Shannon Meyler reviewed it critically for important intellectual content. Alexa Gallagher reviewed it critically for important intellectual content. Tina Cardona reviewed it critically for important intellectual content. Benjamin Ellis reviewed it critically for important intellectual content. Jennifer Ellis final approval of the version to be published. Michael Holton final approval of the version to be published. The authors received no specific funding for this work. Some of the authors of this letter (EA, JE, MH) have testified on behalf of defendants in asbestos and talcum powder litigation matters. No law firm was involved in the writing of this letter, and it was not written for purposes of litigation. Data sharing not applicable to this article as no datasets were generated or analysed during the current study.

With the simultaneous rise in coastal flooding risks projected by current climate models and the escalating demands placed on urban infrastructure by population expansion, there is an urgent need for resilient solutions to address these challenges. In response, the adoption of nature-based solutions (NbS) and natural and nature-based features (NNBF) has gained traction as promising, cost-efficient approaches to bolster coastal resilience while offering additional economic, social, and environmental benefits as compared with traditional “gray” infrastructure. While progress has been made in developing and documenting NbS and NNBF approaches for flood risk management globally, uncertainties persist regarding their practical application and effectiveness in highly urbanized coastal environments. Therefore, the objective of this study was to examine the current understanding of NNBF for coastal resilience, providing insights into their potential applications and opportunities in urban coastal settings. To meet this objective, an NNBF principled approach was applied using the City of Boston coastal storm risk management study as an illustrative example. The initial phases of the NNBF guidelines framework was an effective means of organizing and communicating information relevant to the identification and down selection of NNBF alternatives for the region. This study provides valuable insights into the challenges and opportunities of incorporating innovative NbS and NNBF approaches for flooding risks in coastal urban regions.

This paper presents an in-depth analysis of population-based structural health monitoring applied to offshore wind farms, with a specific focus on a real wind farm. The study quantifies the heterogeneity within the wind turbine population utilising advanced numerical methods. The Fréchet distance is introduced as a key metric to assess the similarity in terms of structural integrity among the turbines considering factors, such as geometry, material properties, topology, and operational conditions. The results revealed a predominant homogeneity with respect across the wind turbines, despite variations in environmental exposure and operational states. Furthermore, the scope of the study is extended to explore the implications of environmental influences, such as corrosion, scour, and marine growth, which are typically unmonitored yet crucial for comprehensive structural assessment. The present paper contributes to the field by demonstrating the feasibility of knowledge transfer in homogeneous wind turbine populations and highlighting the need for detailed similarity assessments in heterogeneous settings. The findings of this study pave the way for better-targeted, smart, and efficient structural health monitoring strategies in renewable energy systems.

Single-point moored floating wind turbines can benefit from the self-alignment of the structure with the prevailing wind direction. However, to be successful, the effects of yaw-drift must be mitigated using effective control strategies during power production. In this work, we investigate sources contributing to yaw drift and propose active control solutions to the problem. The analyses utilize the IEA 15 MW wind turbine mounted on a single-point moored floating foundation. Aero-hydro-servo-elastic simulations using the software 3DFloat are performed under various conditions of wind, waves and current. The results indicate that yaw drift can be actively controlled using nacelle-yaw actuation techniques and individual pitch control of the blades. These approaches effectively align the rotor with the wind direction, increasing the robustness of single-point wind turbines by ensuring increased power production, and maintaining the structural life.

The Dreilindentunnel project is part of a larger development project which establishes a through-going train station in Lucerne. The project includes a 375 m long innercity water crossing under the shallow water area of the Vierwaldstättersee. This paper addresses the comparison of the different tunnel types considered for the water crossing with their main challenges leading to the Immersed Tunnel as the preferred solution. The purpose of this paper is to disseminate knowledge of the Immersed Tunnel Technology and its benefits aiming to inspire owners to assess thoroughly the different tunnel types for each water crossing.

Abstract Large diameter monopiles are the most commonly used foundation type for offshore wind farms. The accurate representation of their response to lateral loading to optimise the required pile penetration plays a crucial role in the design of offshore wind farms. Recently, the PISA method proposed by Burd et al.[6] and Byrne et al. [5] has gained importance in the design of monopiles as it more accurately represents the interaction between the monopile and the soil than standard methods. In the PISA project, sand as well as soft and stiff clay were investigated through monotonic pile tests and the PISA parameters to represent the monopile-soil interaction curves were calibrated for each soil type investigated. Normally, the PISA parameters are derived separately for each soil type and then combined in a 1D model to include the soil stratigraphy. However, soil conditions on site are typically heterogeneous and the interaction between different soil layers with different strengths and stiffnesses should be captured. In order to gain a deeper understanding of the influence of soil stratification on pile deflection curves, this paper presents numerical simulations of a large diameter laterally loaded monopile embedded in layered soil using the finite element method (FEM) including a combination of soft clays and dense sands. Based on the FEM results, PISA parameters for the monopile-soil interaction curves are derived and implemented in a 1D beam model to calculate the pile deflection. The results are compared with a 1D model where the PISA parameters are first derived for the individual soil types and then combined to include the same soil stratigraphy. It is shown that the influence of soil stratification on pile deflection is significant. This paper highlights the need for calibration of PISA parameters considering the actual soil stratigraphy present on site.

Abstract A key challenge in microbiome research is to predict functionality from microbial community composition. As central microbiota functions are determined by bacterial community networks it is important to gain insight into the principles that govern bacteria-bacteria interactions. Here, we focused on growth and metabolic interactions of the Oligo-Mouse-Microbiota (OMM12) synthetic bacterial community, which is increasingly used as model system in gut microbiome research. Using a bottom-up approach, we uncovered the directionality of strain-strain interactions in mono- and pairwise co-culture experiments, as well as in community batch culture. Metabolomics analysis of spent culture supernatant of individual strains in combination with genome-informed pathway reconstruction provided insights into the metabolic potential of the individual community members. Thereby, we could show that the OMM12interaction network is shaped by both, exploitative and interference competitionin vitro.In particular,Enterococcus faecalisKB1 was identified as important driver of community composition by affecting the abundance of several other consortium members. Together, this study gives fundamental insight into key drivers and mechanistic basis of the OMM12interaction network, which serves as knowledge base for future mechanistic studies.