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The present study aims to investigate the effect of various fluids on dam-break flow propagation in a rectangular and horizontal channel under dry bed conditions. Laboratory experiments were carried out to produce dam-break flood waves in a tank by the sudden release of a movable gate that divided the tank into a reservoir and a downstream channel. In these experiments, three different fluids were used as Newtonian fluids in the reservoir: normal water, sunflower oil, and salt water. A digital image processing technique was adopted for the experimental characterization of the dam-break waves. Instantaneous free surface profiles of the dam-break flow were captured by a high-speed camera. Free-surface profiles for different times and time evolution of the flow depths at four selected locations were determined. The types of fluids had an effect on the results due to their specific characteristics such as density and viscosity. Furthermore, numerical simulation of the problem was performed by Reynolds-averaged Navier-Stokes (RANS) and Volume of Fluid (VOF) based software Flow-3D. When the experimental data were compared with the numerical simulation results, there was good agreement for the elapsed time and selected measuring locations.

Objectives: We investigated the associations between religiosity/spirituality and respondents’ changes in their relationships, feelings, thinking, and behaviour during the first wave of the COVID-19 pandemic in the Czech Republic.Methods: A sample of Czech adults (n = 1,434; 48.3 ± 16.4 years; 49.65% women) participated in the online survey. We measured spirituality, religiosity, self-reported changes in relationships, disrupted feelings, and changes in behaviour during the pandemic.Results: Spiritual respondents were more likely to report increased physical activity, sex, reading and self-education, with odds ratios (ORs) ranging from 1.26 (95% confidence interval 1.09–1.46) to 1.56 (1.31–1.86). The combination of spirituality and religiosity led to an increase in the range of ORs to 1.57–2.69. Spiritual and religious participants were less likely to feel the decrease of hope by 70%, while mere spirituality significantly reduced the decrease of hope by only 30%. Religiosity itself led to a lower risk of reporting a disrupted day structure with an OR = 0.74 (0.58–0.95).Conclusion: Religiosity and spirituality separately help people during a pandemic in some areas. Especially their combination has a more positive impact on relationships, feelings, and behaviour.

Background Confinement due to COVID-19 has increased mental ill-health. Few studies unpack the risk and protective factors associated with mental ill-health and addictions that might inform future preparedness. Methods Cross-sectional on-line survey with 37,810 Catalan residents aged 16+ years from 21 April to 20 May 2020 reporting prevalence of mental ill-health and substance use and associated coping strategies and behaviours. Results Weighted prevalence of reported depression, anxiety and lack of mental well-being was, respectively, 23, 26, and 75%, each three-fold higher than before confinement. The use of prescribed hypnosedatives was two-fold and of non-prescribed hypnosedatives ten-fold higher than in 2018. Women, younger adults and students were considerably more likely, and older and retired people considerably less likely to report mental ill-health. High levels of social support, dedicating time to oneself, following a routine, and undertaking relaxing activities were associated with half the likelihood of reported mental ill-health. Worrying about problems living at home, the uncertainty of when normality would return, and job loss were associated with more than one and a half times the likelihood of mental ill-health. With the possible exception of moderately severe and severe depression, length of confinement had no association with reported mental ill-health. Conclusions The trebling of psychiatric symptomatology might lead to either to under-identification of cases and treatment gap, or a saturation of mental health services if these are not matched with prevalence increases. Special attention is needed for the younger adult population. In the presence of potential new confinement, improved mental health literacy of evidence-based coping strategies and resilience building are urgently needed to mitigate mental ill-health.

Background The COVID-19 pandemic is having profound psychological impacts on populations globally, with increasing levels of stress, anxiety, and depression being reported, especially in people with pre-existing medical conditions who appear to be particularly vulnerable. There are limited data on the specific concerns people have about COVID-19 and what these are based on. Methods The aim of this study was to identify and explore the concerns of people with long-term respiratory conditions in the UK regarding the impact of the COVID-19 pandemic and how these concerns were affecting them. We conducted a thematic analysis of free text responses to the question “What are your main concerns about getting coronavirus?”, which was included in the British Lung Foundation/Asthma UK (BLF-AUK) partnership COVID-19 survey, conducted between the 1st and 8th of April 2020. This was during the 3rd week of the UK’s initial ‘social distancing measures’ which included advice to stay at home and only go outside for specific limited reasons. Results 7039 responses were analysed, with respondents from a wide range of age groups (under 17 to over 80), gender, and all UK nations. Respondents reported having asthma (85%), COPD (9%), bronchiectasis (4%), interstitial lung disease (2%), or ‘other’ lung diseases (e.g. lung cancer) (1%). Four main themes were identified: (1) vulnerability to COVID-19; (2) anticipated experience of contracting COVID-19; (3) pervasive uncertainty; and (4) inadequate national response. Conclusions The COVID-19 pandemic is having profound psychological impacts. The concerns we identified largely reflect contextual factors, as well as their subjective experience of the current situation. Hence, key approaches to reducing these concerns require changes to the reality of their situation, and are likely to include (1) helping people optimise their health, limit risk of infection, and access necessities; (2) minimising the negative experience of disease where possible, (3) providing up-to-date, accurate and consistent information, (4) improving the government and healthcare response.

A simulation method for initial-stage sintering was proposed to understand the effect of sintering conditions on the sintering behavior of two particles of different sizes and compositions. This study employed a homogeneous solid solubility system of Cu-Ni. The sintering experiments were performed with two spherical Cu-Ni particles in contact, and the sintered particles were observed by SEM and EDX. It was confirmed that the sintered particles always form a curved neck and copper was the dominant component in the neck.The proposed simulation method, in which the model for two particles of identical composition was modified, involves several mass transport mechanisms: surface diffusion, volume diffusion, grain-boundary diffusion, evaporation-condensation and, newly, grain growth. The sintering behavior of Cu-Ni particles was simulated using the proposed method and the results were highly similar to the experimental results. It was also found that grain growth was not negligible in initial-stage sintering, and that shrinkage and grain growth responded sensitively to sintering conditions. Consequently, by analysis of these simulation results, it is possible to understand the mechanism of sintering two spherical particles of different compositions and to determine the optimum sintering conditions.† This report was originally printed in J. Soc. Powder Technology, Japan, 28(2), 202-210 (2002) in Japanese, before being translated into English by KONA Editorial Committee with the permission of the editorial committee of the Soc. Chemical Engineers, Japan.