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This paper provides a summary of the work done within Phase III of the Offshore Code Comparison Collaboration, Continued, with Correlation and unCertainty (OC6) project, under the International Energy Agency Wind Technology Collaboration Programme Task 30. This phase focused on validating the aerodynamic loading on a wind turbine rotor undergoing large motion caused by a floating support structure. Numerical models of the Technical University of Denmark 10¿MW reference wind turbine were validated using measurement data from a 1:75 scale test performed during the UNsteady Aerodynamics for FLOating Wind (UNAFLOW) project and a follow-on experimental campaign, both performed at the Politecnico di Milano wind tunnel. Validation of the models was performed by comparing the loads for steady (fixed platform) and unsteady (harmonic motion of the platform) wind conditions. For the unsteady wind conditions, the platform was forced to oscillate in the surge and pitch directions under several frequencies and amplitudes. These oscillations result in a wind variation that impacts the rotor loads (e.g., thrust and torque). For the conditions studied in these tests, the system aerodynamic response was almost steady. Only a small hysteresis in airfoil performance undergoing angle of attack variations in attached flow was observed. During the experiments, the rotor speed and blade pitch angle were held constant. However, in real wind turbine operating conditions, the surge and pitch variations would result in rotor speed variations and/or blade pitch actuations, depending on the wind turbine controller region that the system is operating. Additional simulations with these control parameters were conducted to verify the fidelity of different models. Participant results showed, in general, a good agreement with the experimental measurements and the need to account for dynamic inflow when there are changes in the flow conditions due to the rotor speed variations or blade pitch actuations in response to surge and pitch motion. Numerical models not accounting for dynamic inflow effects predicted rotor loads that were 9¿% lower in amplitude during rotor speed variations and 18¿% higher in amplitude during blade pitch actuations. This research has been supported by the office of Energy Efficiency and Renewable Energy (grant no. DE-AC36-08GO28308). Peer Reviewed Roger Bergua1, Amy Robertson1, Jason Jonkman1, Emmanuel Branlard1, Alessandro Fontanella2, Marco Belloli2, Paolo Schito2, Alberto Zasso2, Giacomo Persico3, Andrea Sanvito3, Ervin Amet4, Cédric Brun5, Guillén Campaña-Alonso6, Raquel Martín-San-Román6, Ruolin Cai7, Jifeng Cai7, Quan Qian8, Wen Maoshi8, Alec Beardsell9, Georg Pirrung10, Néstor Ramos-García10, Wei Shi11, Jie Fu11, Rémi Corniglion12, Anaïs Lovera12, Josean Galván13, Tor Anders Nygaard14, Carlos Renan dos Santos14, Philippe Gilbert15, Pierre-Antoine Joulin15, Frédéric Blondel15, Eelco Frickel16, Peng Chen17, Zhiqiang Hu17, Ronan Boisard18, Kutay Yilmazlar19, Alessandro Croce19, Violette Harnois20, Lijun Zhang21, Ye Li21, Ander Aristondo22, Iñigo Mendikoa Alonso22, Simone Mancini23, Koen Boorsma23, Feike Savenije23, David Marten24, Rodrigo Soto-Valle24, Christian W. Schulz25, Stefan Netzband25, Alessandro Bianchini26, Francesco Papi26, Stefano Cioni26, Pau Trubat27, Daniel Alarcon27, Climent Molins27, Marion Cormier28, Konstantin Brüker28, Thorsten Lutz28, Qing Xiao29, Zhongsheng Deng29, Florence Haudin30, and Akhilesh Goveas31 1National Wind Technology Center, National Renewable Energy Laboratory, Golden, CO 80401, USA 2Department of Mechanical Engineering, Politecnico di Milano, Milan 20156, Italy 3Laboratory of Fluid-Machines, Dipartimento di Energia, Politecnico di Milano, Milan 20156, Italy 4Wind Department, Bureau Veritas, Paris 92937, France 5Marine Division, Research Department, Bureau Veritas, Saint-Herblain 44818, France 6Wind Turbine Technologies, Centro Nacional de Energías Renovables, Sarriguren 31621, Spain 7Integrated Simulation Department, China General Certification Center, Beijing 100013, China 8Research Institute, China State Shipbuilding Corporation, Chongqing 401122, China 9Offshore Technology Department, DNV, Bristol BS2 0PS, UK 10Department of Wind Energy, Technical University of Denmark, Lyngby 2800, Denmark 11State Key Laboratory of Coastal and Offshore Engineering, Dalian University of Technology, Dalian 116024, China 12Département Electrotechnique et Mécanique des Structures, Électricité de France, Paris 91120, France 13Wind Energy Department, eureka!, Errigoiti 48309, Spain 14Department of Wind Energy, Institute for Energy Technology, Kjeller 2027, Norway 15Département Mécanique des Fluides, IFP Energies nouvelles, Rueil-Malmaison 92852, France 16Research and Development, Maritime Research Institute Netherlands, Wageningen 6708, the Netherlands 17Marine, Offshore and Subsea Technology, Newcastle University, Newcastle NE1 7RU, UK 18Aerodynamic Department, Office National d’Etudes et de Recherches Aérospatiales, Paris 92190, France 19Department of Aerospace Science and Technology, Politecnico di Milano, Milan 20156, Italy 20Floating Offshore Group, PRINCIPIA, La Ciotat 13600, France 21Wind Energy Group, Shanghai Jiao Tong University, Shanghai 200240, China 22Department of Offshore Renewable Energy, Tecnalia Research & Innovation, Donostia-San Sebastián 20009, Spain 23Wind Energy Department, Netherlands Organisation for Applied Scientific Research, Petten 1755, the Netherlands 24Wind Energy Department, Technische Universität Berlin, 10623 Berlin, Germany 25Institute for Fluid Dynamics and Ship Theory, Hamburg University of Technology, 21073 Hamburg, Germany 26Department of Industrial Engineering, University of Florence, Florence 50139, Italy

This study reports the results of the second round of analyses of the OC6 project Phase III. While the first round investigated rotor aerodynamic loading, here focus is given to the wake behavior of a floating wind turbine under large motion. Wind tunnel experimental data from the UNsteady Aerodynamics for FLOating Wind (UNAFLOW) project are compared with the results of simulations provided by participants with methods and codes of different levels of fidelity. The effect of platform motion both on the near and the far wake is investigated. More specifically, the behavior of tip vortices in the near wake is evaluated through multiple metrics, such as streamwise position, core radius, convection velocity, and circulation. Additionally, the onset of velocity oscillations in the far wake is analyzed because this can have a negative effect on stability and loading of downstream rotors. Results in the near wake for unsteady cases confirm that simulations and experiments tend to diverge from the expected linearized quasi-steady behavior when the rotor reduced frequency increases over 0.5. Additionally, differences across the simulations become significant, suggesting that further efforts are required to tune the currently available methodologies in order to correctly evaluate the aerodynamic response of a floating wind turbine in unsteady conditions. Regarding the far wake, it is seen that, in some conditions, numerical methods over-predict the impact of platform motion on the velocity fluctuations. Moreover, results suggest that, different from original expectations about a faster wake recovery in a floating wind turbine, the effect of platform motion on the far wake seems to be limited or even oriented to the generation of a wake less prone to dissipation.

Although it is clear that many of the major contemporary social problems center on the extent to which social institutions do or do not function as they are meant to do, it is still unclear exactly what the function of a social institution is—and thus when this function is undermined. This paper presents and defends a novel theory of social functionalism—presentist social functionalism—to answer these questions. According to this theory, the function of social institutions is grounded in those of their features that, in the current cultural environment, increase their chances to survive or reproduce. To bring out the fruitfulness of this account, the paper analyzes the (still controversial) question of the function of corporations, and shows that present social functionalism (a) points to the kinds of data that would be helpful to determine this function, (b) brings up hitherto overlooked theoretical possibilities, and (c) allows for the clearer assessment and handling of corporate corruption.

Moderate endurance exercise leads to an improvement in cardiovascular performance, stress resilience, and blood function. However, the influence of chronic endurance exercise over several hours or days is still largely unclear. We examined the influence of a non-stop 160.9/230 km ultramarathon on body composition, stress/cardiac response, and nutrition parameters. Blood samples were drawn before (pre) and after the race (post) and analyzed for ghrelin, insulin, irisin, glucagon, cortisol, kynurenine, neopterin, and total antioxidant capacity. Additional measurements included heart function by echocardiography, nutrition questionnaires, and body impedance analyses. Of the 28 included ultra-runners (7f/21m), 16 participants dropped out during the race. The remaining 12 finishers (2f/10m) showed depletion of antioxidative capacities and increased inflammation/stress (neopterin/cortisol), while energy metabolism (insulin/glucagon/ghrelin) remained unchanged despite a high negative energy balance. Free fat mass, protein, and mineral content decreased and echocardiography revealed a lower stroke volume, left end diastolic volume, and ejection fraction post race. Optimizing nutrition (high-density protein-rich diet) during the race may attenuate the observed catabolic and inflammatory effects induced by ultramarathon running. As a rapidly growing discipline, new strategies for health prevention and extensive monitoring are needed to optimize the athletes’ performance.

Genetic introgression of farmed salmon into wild populations can damage the genetic integrity of wild stocks and is therefore considered as an environmental threat. One possible solution is to induce sterility in farmed salmon. We have searched for proteins potentially essential for germline survival in Atlantic salmon. One of these is the argonaute protein Piwil1, known to be required for germ cell survival. To examine Piwil1 function in salmon, we induced indels in the N domain by CRISPR-Cas9. The encoded domain is present in all vertebrate Piwi proteins and has been linked to Tdrd1 protein interaction and PAZ lobe structure. The F0 founder generation of piwil1 crispant males and females displayed a mosaic pattern of piwil1 mutations, exhibiting highly mutated alleles (53%–97%) in their fin gDNA samples. In general, piwil1 crispants carried germ cells, went through puberty and became fertile, although a transient and partial germ cell loss and delays during the spermatogenic process were observed in many male crispants, suggesting that Piwil1 functions during salmon spermatogenesis. By crossing highly mutated F0 founders, we produced F1 fish with a mixture of: loss-of-function alleles (−); functional in frame mutated alleles (+) and wt alleles (+). In F1, all piwil1−/− fish lacked germ cells, while piwil1+/+ siblings showed normal ovaries and testes. Yet, most juvenile F1 piwil1+/−males and females displayed an intermediate phenotype with a higher somatic/germ cell ratio without an increase in germ cell apoptosis, suggestive of a gene dose effect on the number of germ cells and/or insufficient replacement of lost germ cells in heterozygous fish. Interestingly, the two longest in-frame indels in the N domain also ensured germ cell loss. Hence, the loss of 4–6 aa in this region Phe130-Ser136 may result in crucial changes of the protein structure, potentially affecting piRNA binding of the PAZ lobe, and/or affecting the binding of Piwil1 interacting proteins such as Tdrd protein, with critical consequences for the survival of primordial germ cells. In conclusion, we show that loss of piwil1 leads to loss of germ cells in salmon and that part of the N domain of Piwil1 is crucial for its function.

Graphical abstract Due to growing concern about organic micropollutants and their transformation products (TP) in surface and drinking water, reliable identification of unknowns is required. Here, we demonstrate how non-target liquid chromatography (LC)-high-resolution tandem mass spectrometry (MS/MS) and the feature-based molecular networking (FBMN) workflow provide insight into water samples from four riverbank filtration sites with different redox conditions. First, FBMN prioritized and connected drinking water relevant and seasonally dependent compounds based on a modification-aware MS/MS cosine similarity. Within the resulting molecular networks, forty-three compounds were annotated. Here, carbamazepine, sartans, and their respective TP were investigated exemplarily. With chromatographic information and spectral similarity, four additional TP (dealkylated valsartan, dealkylated irbesartan, two oxygenated irbesartan isomers) and olmesartan were identified and partly verified with an authentic standard. In this study, sartans and TP were investigated and grouped regarding their removal behavior under different redox conditions and seasons for the first time. Antihypertensives were grouped into compounds being well removed during riverbank filtration, those primarily removed under anoxic conditions, and rather persistent compounds. Observed seasonal variations were mainly limited to varying river water concentrations. FBMN is a powerful tool for identifying previously unknown or unexpected compounds and their TP in water samples by non-target analysis. Supplementary Information The online version contains supplementary material available at 10.1007/s00216-021-03500-7.

Introduction COVID-19 is a multi-systemic disease which can target the lungs and the cardiovascular system and can also affect parts of the brain for prolonged periods of time. Even healthy athletes without comorbidities can be psychologically affected long-term by COVID-19. Objective This study aimed to investigate athletes’ perceived mental stress and recovery levels in daily life, and their maximal aerobic power, at three different time points, post COVID-19. Methods In total, 99 athletes (62.6% male), who had been infected by COVID-19, filled out the Recovery Stress Questionnaire for Athletes (REST-Q-Sport) and completed cardiopulmonary exercise testing (endpoint maximal aerobic power output (Pmax)) at the initial screening (t1: 4 months after infection). Follow-up assessments occurred three (t2, n = 37) and seven months after t1 (t3, n = 19). Results Subgroup means from the Recovery category were significantly below the reference value of four at all three time points, except “General Recovery” (3.76 (± 0.96), p = 0.275, d = 0.968) at t3.”Overtiredness” (2.34 (± 1.27), p = 0.020, r = 0.224) was significantly above the reference value of two at t1, while all other Stress subgroups were not significantly different from the reference value or were significantly below the maximum threshold of two at t1, t2 and t3. Spearman’s ρ revealed a negative association between Pmax and the subcategories of stress (ρ = -0.54 to ρ = -0.11, p < 0.050), and positive correlations between Pmax and “Somatic Recovery” (ρ = 0.43, p < 0.001) and “General Recovery” (ρ = 0.23, p = 0.040) at t1. Pmax (t1: 3.83 (± 0.99), t2: 3.78 (± 1.14), β = 0.06, p < 0.003) increased significantly from t1 to t2. In addition, REST-Q-Sport indicated a decrease in "Sleep" (t2 = 2.35 (± 0.62), t3 = 2.28(± 0.61), β = -0.18, p < 0.023) at t3, when compared to t2. Conclusion The perceived recovery seems to be negatively affected in post COVID-19 athletes. Physical performance post COVID-19 correlates with both “Emotional and Somatic Stress” and “Somatic and General Recovery”, indicating potential mental and physical benefits of exercise. While it is evident that COVID-19, like other viral infections, may have an influence on physical performance, monitoring stress and recovery perceptions of athletes is critical to facilitate their return-to-sports, while minimizing long-term COVID-19 induced negative effects like the athletic objective and subjective perceived recovery and stress levels.

Lumpfish is the most important cleanerfish species in Atlantic salmon farming. Detailed information on the gonadal maturation process is a prerequisite for year-round production of juvenile lumpfish. In the present study we have described physiological, morphological and endocrine events associated with the annual reproductive cycle in lumpfish of both sexes. Female lumpfish matured at a body weight close to 2 kg and were capable of spawning two egg batches, one in February/March and one in May/June. Male lumpfish could be stripped for sperm most of the year. The appearance of spawning males with high 11-KT concentrations and clearly developed secondary sexual characters was synchronized with female spawning. From the onset of maturation to the periovulatory stages in females, pituitary transcript levels of gnrhr2ba1 and lhb increased in a correlated manner, together with an increase in GSI and in circulating E2 concentrations. In contrast, a high individual variation of fshb transcript levels was observed, potentially reflecting the bimodal oocyte development with oocytes at different developmental stages present in the ovary at the same time. The onset of pubertal testis growth concurred with an increase in pituitary fshb and lhb transcript levels, while plasma 11-KT concentrations increased at later stages, correlating with a gnrhr2ba1 increase. It appears that spermatogenesis and testis growth is regulated by Fsh and can proceed in the presence of low androgen levels. publishedVersion

Reversed-phase liquid chromatography (RPLC) used for water analysis is not ideal for the analysis of highly polar and ionic contaminants because of low retention. Capillary electrophoresis (CE), on the other hand, is perfectly suited for the separation of ionic compounds but rarely applied in environmental analysis due to the weak concentration sensitivity when coupled to mass spectrometry (MS). However, novel interface designs and MS technology strongly improve the sensitivity. Here, a method is presented enabling the screening of anionic micropollutants in drinking water without sample pretreatment by coupling of CE to an Orbitrap mass spectrometer by a nanoflow sheath liquid interface. Targeted analysis of halogenated acetic acids, trifluoromethanesulfonic acid, and perfluorooctanoic and perfluorooctanesulfonic acid was conducted in drinking water samples which were chlorinated for disinfection. A bare fused silica capillary with an optimized background electrolyte (BGE) for separation consisting of 10% acetic acid with 10% isopropanol with large volume sample injection and optimized interface parameters offer limits of quantification in the range of 0.993) and repeatability (14% standard deviation in area). Concentrations of the target analytes ranged from 0.1 to 6.2 μg/L in the water samples. Masses corresponding to halogenated methanesulfonic acids have been found as suspects and were subsequently verified by standards. Mono-, dichloro-, and bromochloro methanesulfonic acid were quantified in a range of 0.2 to 3.6 μg/L. Furthermore, five sulfonic acids, four organosulfates, and the artificial sweeteners acesulfame and cyclamate as well as inorganics such as halides, halogenates, phosphate, and sulfate could be determined as suspects among more than 300 features in a non-targeted screening. Overall, this approach demonstrates the great potential of CE-nanoESI-MS for the screening of ionic contaminants in environmental samples, complementary to chromatographic approaches. Electronic supplementary material The online version of this article (10.1007/s00216-020-02525-8) contains supplementary material, which is available to authorized users.