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Although the relationship between the environmental factors, such as weather conditions and air pollution, and COVID-19 case fatality rate (CFR) has been found, the impacts of these factors to which infected cases are exposed at different infectious stages (e.g., virus exposure time, incubation period, and at or after symptom onset) are still unknown. Understanding this link can help reduce mortality rates. During the first wave of COVID-19 in the United Kingdom (UK), the CFR varied widely between and among the four countries of the UK, allowing such differential impacts to be assessed. We developed a generalized linear mixed-effect model combined with distributed lag nonlinear models to estimate the odds ratio of the weather factors (i.e., temperature, sunlight, relative humidity, and rainfall) and air pollution (i.e., ozone, N O 2 , S O 2 , CO , P M 10 and P M 2.5 ) using data between March 26, 2020 and September 15, 2020 in the UK. After retrospectively time adjusted CFR was estimated using back-projection technique, the stepwise model selection method was used to choose the best model based on Akaike information criteria and the closeness between the predicted and observed values of CFR. The risk of death reached its maximum level when the low temperature (6 °C) occurred 1 day before (OR 1.59; 95% CI 1.52–1.63), prolonged sunlight duration (11–14 h) 3 days after (OR 1.24; 95% CI 1.18–1.30) and increased P M 2.5 (19 μg/m3) 1 day after the onset of symptom (OR 1.12; 95% CI 1.09–1.16). After reopening, many COVID-19 cases will be identified after their symptoms appear. The findings highlight the importance of designing different preventive measures against severe illness or death considering the time before and after symptom onset. [ABSTRACT FROM AUTHOR]

The prevalence of elderly dementia and work-related back neck pain is high, and so is the associated cost. Is dementia, which can take 20–30 years to develop, linked to musculoskeletal problems earlier in life? Classic Chinese Medicine Governor Vessel (GV) theory has in fact detailed a correlation, but its acceptance appears to be influenced and even limited by some inconsistences in the literature. This study involved a nationwide online questionnaire of 381 practicing acupuncturists to investigate GV's usage and impact on brain function. The survey covers areas of the acupuncturist's experience, perception of GV usage, related symptoms, needling concerns and correlations with brain function. 39 completed questionnaires were returned, of which 38 were GV users, and nearly three quarters of respondents accepted that GV influences brain function. Only two respondents rejected this influence, but here several inconsistencies were found. The associations with GV were predominately found to be with the spine, kidney, and brain. Indications from practitioners suggested numerous forms of clinical usage of GV, predominately on spinal, cognitive and qi-blood movement issues. GV influence on the brain was accepted by most respondents with only a few expressing uncertainty. Further worldwide, larger population, in-depth studies and trials are needed to fully establish and expand upon these findings. [ABSTRACT FROM AUTHOR]

• • Integration of concentrated solar collectors with heat pump heating system has been studied. • • Concentrator solar collector leads to potentially 50% size reduction. • • Using concentrated solar collector obtains yearly seasonal performance factor of 4.7. • • Concentrated solar collector enables application of the system to low solar irradiance. Solar assisted air source heat pump heating systems are capable of achieving green heating where solar availability essentially affects its operation performance and application potentials, especially in higher-latitude regions, such as UK. Compound parabolic concentrator solar collectors can achieve high collector efficiency at high hot water temperature, benefitting to improve solar collection and corresponding thermal energy storage capacities. Though compound parabolic concentrator solar collectors have been widely investigated, application of such collector for solar assisted air source heat pump system is not studied yet. The paper reports numerical simulations of solar assisted air source heat pump heating systems that integrate compound parabolic concentrator-capillary tube solar collectors for domestic heating in the UK. The results show that, for the same seasonal performance factor, the size of the concentrated solar collector required is 12 m2 whereas the size of the flat plate solar collector required is 18 m2. This suggests one third reduction in the size of solar collector, significant reduction in cost and convenience for installation. The results also show the potential to further reduce the size of the concentrated solar collector to 9 m2 or less. The high collector efficiency of the compound parabolic concentrator-capillary tube solar collector enables much small size of solar collector, significantly lower cost and convenient for installation and wide rollout of solar assisted air source heat pump heating system to locations where solar irradiance is relatively lower. [ABSTRACT FROM AUTHOR]

• Three indirect expansion solar assisted air source heat pumps are numerically studied. • Space heating and hot water performances of three heat pumps are examined in detail. • Their yearly seasonal performance factors are higher than 4.4 in high latitude regions. • The heat pumps are economically applicable in high latitude regions. To achieve the goal set for net-zero emissions of greenhouse gases in the UK by 2050, the domestic heating must be decarbonised. Solar assisted air source heat pumps, integrating solar collector, thermal energy storage tank and heat pump, offers a promising alternative application under the UK weather conditions. Literature review shows that investigations of solar assisted air source heat pumps in the regions like the UK are still insufficient. The serial, parallel and dual-source indirect expansion solar assisted air source heat pumps are modelled and simulated under the weather conditions in London using TRNSYS to investigate the operation performance over a typical year. These three heat pumps are applied to provide space heating and hot water of 300 L per day for a typical single-family house. The simulation results show comparisons of the three systems. The serial type heat pump shows the highest seasonal performance factor of 5.5, but requiring the largest sizes of the solar collector and thermal energy storage tank. The dual-source and parallel type heat pumps show slightly lower seasonal performance factors of 4.4 and 4.5, respectively, requiring smaller sizes of solar collector and thermal energy storage tank. Furthermore, the results show that the air source part contributes to an important proportion of the heat provision and stable operation of the systems. The yearly seasonal performance factor higher than 4.4 achievable by the three heat pumps suggests that they are potentially applied in the regions with relatively lower solar irradiance. The economic analyses indicate that the parallel and dual-source type heat pumps provide good alternatives to replace the gas-boiler heating system. [ABSTRACT FROM AUTHOR]