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E. Begović, C. Bertorello, F. Çakıcı, E. Kahramanoğlu, B. Rinauro

In this paper, the validation of the hybrid frequency–time domain method for the assessment of hard chine displacement hull from vertical motions is presented. Excitation and hydrodynamic coefficients in regular waves are obtained from the 3D panel method by Hydrostar® software, while coupled heave and pitch motions are calculated in the time domain by applying the Cummins equations. Experiments using a 1:15 scale model of a “low-drag” small craft are performed in irregular head and following waves at Froude numbers Fr: 0.2, 0.4, and 0.6 at University of Naples Federico II, Italy. Results obtained by hybrid frequency–time domain simulations for heave, pitch, and vertical accelerations at center of gravity and bow are compared with experimental data and showed high accuracy.

Ayman Alhamdow, Y. Essig, A. Krais, P. Gustavsson, H. Tinnerberg, C. Lindh, J. Hagberg, P. Graff et al.

Objectives Exposure to high-molecular-weight polycyclic aromatic hydrocarbons (PAHs) may cause cancer in chimney sweeps and creosote-exposed workers, however, knowledge about exposure to low-molecular-weight PAHs in relation to cancer risk is limited. In this study, we aimed to investigate occupational exposure to the low-molecular-weight PAHs phenanthrene and fluorene in relation to different cancer biomarkers. Methods We recruited 151 chimney sweeps, 19 creosote-exposed workers and 152 unexposed workers (controls), all men. We measured monohydroxylated metabolites of phenanthrene and fluorene in urine using liquid chromatography coupled to tandem mass spectrometry. We measured, in peripheral blood, the cancer biomarkers telomere length and mitochondrial DNA copy number using quantitative PCR; and DNA methylation of F2RL3 and AHRR using pyrosequencing. Results Median PAH metabolite concentrations were higher among chimney sweeps (up to 3 times) and creosote-exposed workers (up to 353 times), compared with controls (p<0.001; adjusted for age and smoking). ∑OH-fluorene (sum of 2-hydroxyfluorene and 3-hydroxyfluorene) showed inverse associations with percentage DNA methylation of F2RL3 and AHRR in chimney sweeps (B (95% CI)=–2.7 (–3.9 to –1.5) for F2RL3_cg03636183, and –7.1 (–9.6 to –4.7) for AHRR_cg05575921: adjusted for age and smoking), but not in creosote-exposed workers. In addition, ∑OH-fluorene showed a 42% mediation effect on the inverse association between being a chimney sweep and DNA methylation of AHRR CpG2. Conclusions Chimney sweeps and creosote-exposed workers were occupationally exposed to low-molecular-weight PAHs. Increasing fluorene exposure, among chimney sweeps, was associated with lower DNA methylation of F2RL3 and AHRR, markers for increased lung cancer risk. These findings warrant further investigation of fluorene exposure and toxicity.

S. Willach, H. Lutze, H. Somnitz, Jens Terhalle, Nenad Stojanović, Michelle Lüling, M. Jochmann, T. Hofstetter et al.

Oxidative processes frequently contribute to organic pollutant degradation in natural and engineered systems such as during the remediation of contaminated sites and in water treatment processes. Because a systematic characterization of abiotic reactions of organic pollutants with oxidants such as ozonation or hydroxyl radicals by compound-specific stable isotope analysis (CSIA) is lacking, stable isotope-based approaches have rarely been applied for the elucidation of mechanisms of such transformations. Here, we investigated the carbon isotope fractionation associated with the oxidation of benzene and several methylated and methoxylated analogs, namely toluene, three xylene isomers, mesitylene and anisole, and determined their carbon isotope enrichments factors (εC) for reactions with ozone (εC = -3.6 ‰ to -4.6 ‰) and hydroxyl radicals (εC = 0.0 to -1.2 ‰). The differences in isotope fractionation can be used to elucidate the contribution of the reactions with ozone or hydroxyl radicals to overall transformation. Derivation of apparent kinetic isotope effects (AKIEs) for the reaction with ozone, however, was nontrivial due to challenges in assigning reactive positions in the probe compounds for the monodentate attack leading to an ozone adduct. We present several options for this step and compare the outcome to quantum chemical characterizations of ozone adducts. Our data show that a general assignment of reactive positions for reactions of ozone with aromatic carbon in ortho-, meta- or para-positions is not feasible and that AKIEs of this reaction should be derived on a compound-by-compound basis.

A. Desvars-Larrive, Elma Dervić, Nina Haug, T. Niederkrotenthaler, Jiaying Chen, Anna Di Natale, J. Lasser, D. Gliga et al.

In response to the COVID-19 pandemic, governments have implemented a wide range of non-pharmaceutical interventions (NPIs). Monitoring and documenting government strategies during the COVID-19 crisis is crucial to understand the progression of the epidemic. Following a content analysis strategy of existing public information sources, we developed a specific hierarchical coding scheme for NPIs. We generated a comprehensive structured dataset of government interventions and their respective timelines of implementation. To improve transparency and motivate collaborative validation process, information sources are shared via an open library. We also provide codes that enable users to visualise the dataset. Standardization and structure of the dataset facilitate inter-country comparison and the assessment of the impacts of different NPI categories on the epidemic parameters, population health indicators, the economy, and human rights, among others. This dataset provides an in-depth insight of the government strategies and can be a valuable tool for developing relevant preparedness plans for pandemic. We intend to further develop and update this dataset until the end of December 2020. Measurement(s) time at medical intervention • medical intervention Technology Type(s) digital curation • content analysis strategy of existing information sources Factor Type(s) non-pharmaceutical intervention • date Sample Characteristic - Location global Measurement(s) time at medical intervention • medical intervention Technology Type(s) digital curation • content analysis strategy of existing information sources Factor Type(s) non-pharmaceutical intervention • date Sample Characteristic - Location global Machine-accessible metadata file describing the reported data: https://doi.org/10.6084/m9.figshare.12668792

I. Tanackov, I. Pavkov, Željko Stević

An arbitrary univariate polynomial of nth degree has n sequences. The sequences are systematized into classes. All the values of the first class sequence are obtained by Newton’s polynomial of nth degree. Furthermore, the values of all sequences for each class are calculated by Newton’s identities. In other words, the sequences are formed without calculation of polynomial roots. The New-nacci method is used for the calculation of the roots of an nth-degree univariate polynomial using radicals and limits of successive members of sequences. In such an approach as is presented in this paper, limit play a catalytic–theoretical role. Moreover, only four basic algebraic operations are sufficient to calculate real roots. Radicals are necessary for calculating conjugated complex roots. The partial limitations of the New-nacci method may appear from the decadal polynomial. In the case that an arbitrary univariate polynomial of nth degree (n ≥ 10) has five or more conjugated complex roots, the roots of the polynomial cannot be calculated due to Abel’s impossibility theorem. The second phase of the New-nacci method solves this problem as well. This paper is focused on solving the roots of the quintic equation. The method is verified by applying it to the quintic polynomial with all real roots and the Degen–Abel polynomial, dating from 1821.

S. Endo, Jakob Fröhner, Selma Musić, S. Hirche, P. Beckerle

In the advent of intelligent robotic tools for physically assisting humans, user experience, and intuitiveness in particular have become important features for control designs. However, existing works predominantly focus on performance-related measures for evaluating control systems as the subjective experience of a user by large cannot be directly observed. In this study, we therefore focus on agency-related interactions between control and embodiment in the context of physical human-machine interaction. By applying an intentional binding paradigm in a virtual, machine-assisted reaching task, we evaluate how the sense of agency of able-bodied humans is modulated by assistive force characteristics of a physically coupled device. In addition to measuring how assistive force profiles influence the sense of agency with intentional binding, we analyzed the sense of agency using a questionnaire. Remarkably, our participants reported to experience stronger agency when being appropriately assisted, although they contributed less to the control task. This is substantiated by the overall consistency of intentional binding results and the self-reported sense of agency. Our results confirm the fundamental feasibility of the sense of agency to objectively evaluate the quality of human-in-the-loop control for assistive technologies. While the underlying mechanisms causing the perceptual bias observed in the intentional binding paradigm are still to be understood, we believe that this study distinctly contributes to demonstrating how the sense of agency characterizes intuitiveness of assistance in physical human-machine interaction.

Introduction: The challenges faced by visually impaired people in their efforts to integrate themselves into the labor market and the general position of persons with disabilities, regarding their employment and social security, is extremely difficult. Employment is the best safeguard against social exclusion and one of the main ways to achieve a full involvement in the society of the visually impaired people.Methods: The research was conducted on a sample of 25 visually impaired people employed at “TMP” d.o.o. Sarajevo. The study was used as a cross-sectional survey method wherein data were collected through appropriate survey instruments, using a modified survey questionnaire.Results: Out of the total number of respondents, 48% are male and 52% are female. The majority of respondents use other persons’ assistance when moving (n = 16). The largest number of respondents had 100% visual impairment (n = 17). The majority of subjects have no strenuous physical activity. The largest number of respondents during the previous week walked for at least 10 minutes, in the sequence of all 7 days and was driven in motor vehicles. When doing household chores, 56% of respondents said they had no difficulty. The most common difficulties in recreation, sports and physical activity in leisure time, that were encountered by 32% of respondents, are poor sound signalling and difficulties of visual nature, though 68% of respondents said that they had no difficulty in their recreational activities.Conclusion: The daily activities of employed visually impaired persons have a positive impact on their quality of life. Various are occupations of visually impaired people that improve their quality of life.

M. Sartelli, D. Weber, Y. Kluger, L. Ansaloni, F. Coccolini, F. Abu-Zidan, G. Augustin, O. Ben-Ishay et al.

Acute colonic diverticulitis is one of the most common clinical conditions encountered by surgeons in the acute setting. An international multidisciplinary panel of experts from the World Society of Emergency Surgery (WSES) updated its guidelines for management of acute left-sided colonic diverticulitis (ALCD) according to the most recent available literature. The update includes recent changes introduced in the management of ALCD. The new update has been further integrated with advances in acute right-sided colonic diverticulitis (ARCD) that is more common than ALCD in select regions of the world.

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