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Abstract Leisure engagement has potential to slow health and functional decline in older age. However, the benefits of different leisure domains for different aspects of aging remains unclear. In 8771 older adults from the Health and Retirement Study (a longitudinal panel study), we measured engagement in physical, creative, cognitive, and community activities. Outcome-wide analyses used 23 aging experiences across seven domains eight years later (daily functioning, physical fitness, long-term physical health problems, heart health, weight, sleep, subjective perceptions of health). Physical activity was related to more positive experiences in all domains but heart health eight years later. Creative engagement was positively related to aging experiences in four domains longitudinally. Cognitive and community engagement were less consistently related to aging experiences. Physical and creative activities may influence important aging metrics, reducing age-related decline and keeping older adults functionally independent for longer, potentially limiting increasing healthcare costs.

Background A significant rise in mental health disorders was expected during the COVID-19 pandemic. However, referrals to mental health services dropped for several months before rising to pre-pandemic levels. Aims To identify trajectories of incidence and risk factors for common mental disorders among the general population during 14 months of the COVID-19 pandemic, to inform potential mental health service needs. Method A cohort of 33 703 adults in England in the University College London COVID-19 Social Study provided data from March 2020 to May 2021. Growth mixture modelling was used to identify trajectories based on the probability of participants reporting symptoms of depression (Patient Health Questionnaire-9) or anxiety (Generalised Anxiety Disorder-7) in the clinical range, for each month. Sociodemographic and personality-related characteristics associated with each trajectory class were explored. Results Five trajectory classes were identified for depression and anxiety. Participants in the largest class (62%) were very unlikely to report clinically significant symptom levels. Other trajectories represented participants with a high likelihood of clinically significant symptoms throughout, early clinically significant symptoms that reduced over time, clinically significant symptoms that emerged as the pandemic unfolded and a moderate likelihood of clinically significant symptoms throughout. Females, younger adults, carers, those with existing mental health diagnoses, those that socialised frequently pre-pandemic and those with higher neuroticism scores were more likely to experience depression or anxiety. Conclusions Nearly 40% of participants followed trajectories indicating risk of clinically significant symptoms of depression or anxiety. The identified risk factors could inform public health interventions to target individuals at risk in future health emergencies.

Smart meters provide much energy consumption information at the residential level, making it possible to improve short-time load forecasting accuracy by identifying more specific load patterns for each consumer type. This paper proposes a day-ahead load forecasting approach that uses the smart meter data aggregated by residential customers’ power consumption characteristics. First, the long-term trend information and daily fluctuation information are extracted from the residential load time series. According to the load characteristics reflected by the daily load fluctuation information, the residential consumers are clustered into several groups using the K-means algorithm. The non-linear autoregressive neural network is used to forecast each cluster of consumers to capture their specific load patterns. Finally, the aggregated load at the system level is obtained by combining each cluster’s forecasting results. The proposed method’s forecasting performance is evaluated on the data from Irish household customers’ actual smart meters. The outcomes show that the suggested approach can improve forecasting performance under a specific clustering scale.

Driven by the goal of ‘carbon peak, carbon neutrality’, an integrated demand response strategy for integrated electricity–hydrogen energy systems is proposed for low-carbon energy supply parks considering the multi-level and multi-energy characteristics of campus-based microgrids. Firstly, considering the spatial and temporal complementary nature of wind and photovoltaic generation and energy utilization, the energy flow framework of the park is built based on the electricity and hydrogen energy carriers. Clean energy is employed as the main energy supply, and power, heat, cooling, and gas loads are considered energy consumption. Secondly, the operation mechanism of coupled hydrogen storage, hydrogen fuel cell, and carbon capture equipment is analyzed in the two-stage power-to-gas conversion process. Thirdly, considering the operating costs and environmental costs of the park, an integrated demand response dispatch model is constructed for the coupled electricity–hydrogen–carbon system while satisfying the system equipment constraints, network constraints and energy balance constraints of the park system. Finally, Case study in an energy supply park system is implemented. The dispatch results of the integrated demand response with customer participation in the conventional, electricity–hydrogen and electricity–hydrogen–carbon modes are compared to verify the effectiveness of the proposed strategy in renewable accommodation, environmental protection, and economic benefits.

Abstract Adolescent externalising behaviours are associated with numerous long-term negative outcomes, although most research is intervention-based as opposed to risk reduction. Arts engagement has been associated with numerous beneficial factors linked to externalising behaviours, yet direct evidence linking them in longitudinal studies is lacking. Data from the Early Childhood Longitudinal Study were used, with baseline at 5th grade and outcomes measured at 8th grade. Ordinary least squares (OLS) regression was used to examine individual-level associations between extracurricular and school-based arts engagement with externalising behaviours. OLS regression was also used to examine associations between school-level arts classes and facilities with an administrator-reported index of externalising behaviours in the school. All models were adjusted for sociodemographic factors. Individual-level analyses were clustered by school. At the individual level, engaging in a greater number of extracurricular arts activities was associated with fewer externalising behaviours, although there was no association for school-based arts engagement. There were no school-level associations between arts classes or adequate arts facilities and externalising behaviours. Our results suggest extracurricular arts activities may be beneficial in reducing the risk for externalising behaviours, but the relationship is seen at an individual-level of engagement rather than based on school-level provision or facilities.

Abstract Background Social prescribing is a mechanism of connecting patients with non-medical forms of support within the community and has been shown to improve mental health and wellbeing in adult populations. In the last few years, it has been used in child and youth settings with promising results. Currently, pathways are being developed for social prescribing in Child and Adolescent Mental Health Services (CAMHS) to support children and young people on treatment waiting lists. The Wellbeing While Waiting study will evaluate whether social prescribing benefits the mental health and wellbeing of children and young people. Methods This study utilises an observational, hybrid type II implementation-effectiveness design. Up to ten CAMHS who are developing social prescribing pathways as part of a programme run across England with support from the Social Prescribing Youth Network will participate. Outcomes for children and young people receiving social prescribing whilst on CAMHS waiting lists will be compared to a control group recruited prior to the pathway roll-out. Questionnaire data will be collected at baseline, 3 months and 6 months. Primary outcomes for children and young people are mental health symptoms (including anxiety, depression, stress, emotional and behavioural difficulties). Secondary outcomes include: loneliness, resilience, happiness, whether life is worthwhile, life satisfaction, and service use. An implementation strand using questionnaires and interviews will explore the acceptability, feasibility, and suitability of the pathway, potential mechanisms of action and their moderating effects on the outcomes of interest, as well as the perceived impact of social prescribing. Questionnaire data will be analysed mainly using difference-in-differences or controlled interrupted time series analysis. Interview data will be analysed using reflexive thematic analysis. Discussion The Wellbeing While Waiting study will provide the first rigorous evidence of the impact of social prescribing for children and young people on waiting lists for mental health treatment. Findings will help inform the prioritisation, commissioning, and running of social prescribing in other CAMHS. To maximise impact, findings will be available on the study website ( https://sbbresearch.org ) and disseminated via national and international networks. Trial Registration N/A.

High-performance overmodulation strategies for voltage source inverters (VSIs) can further broaden the operation range of machines. Among them, Space Vector Pulse Width Modulation (SVPWM) is worth researching as it performs well in digital implementation. This paper presents a detailed comparison of various SVPWM overmodulation strategies and analysis of their performance. It firstly briefly elaborates fundamental laws of two subspaces of five-phase VSIs. Then, it focuses on several overmodulation strategies. Their corresponding basic principles and main characteristics are researched, and conclusions are given. In addition, differences and relationships between them are proved and summarized. Lastly, comparative simulations and experiments were carried out and verify that in the overmodulation region, the output voltage distortion degree increases with the increase in modulation ratio, and strategies with more control degrees of freedom (CDFs) are capable of better controlling the third harmonic subspace, which means that higher-quality output voltage waveforms would be obtained.

Abstract In this editorial, we consider the current state of loneliness and social isolation research around the world, including knowledge gaps in the empirical literature.

SiC-based motor drives have the advantages of achieving higher efficiency and higher power density than traditional Si-based motor drives, and are gradually being widely used in electric power transmission. Due to different application situations such as oil field and airplane, a long cable is applied between the motor drive and three-phase motor and the distance may exceed hundreds of meters, which will cause serious voltage reflection problem, damaging working life of the motor. Meanwhile, the high slew rate of output voltage created by SiC-based motor drive deteriorates this phenomenon. In order to solve this problem, we first analyze the principle and influencing factors of voltage reflection, and establish the equivalent circuit model of the long cable. Then we put forward design method of LRC passive filter to suppress voltage reflection, and give simulation analysis. At last we built an experimental platform to verify the effectiveness of the LRC passive filter in SiC-based motor drive, and the experimental results show that the LRC passive filter with optimized parameters has good suppression effect of voltage reflection.

Abstract Government enforced restrictions on movement during the COVID-19 pandemic are likely to have had profound impacts on the daily behaviours of many individuals, including physical activity (PA). Given the associations between PA and other health behaviours, changes in PA during the pandemic may have been detrimental for other health behaviours. This study aimed to evaluate whether changes in PA during and after the first national lockdown in the United Kingdom (UK) were associated with concurrent changes in alcohol consumption, sleep, nutrition quality, diet quantity and sedentary time. Data were derived from the UCL COVID-19 Social Study, in which 52,784 adults were followed weekly across 22 weeks of the pandemic from 23rd March to 23rd August 2020. Fixed effects regression models showed that greater PA was positively associated with improved sleep and nutrition quality. However, increases in PA also showed modest associations with increased alcohol consumption and sedentary time. Encouraging people to engage in PA may lead to wider changes in other health behaviours in times of adversity. These associations could be a result of increases in available leisure time for many people during COVID-19 restrictions and are of ongoing importance given the emerging long-term changes to lifestyle and working patterns.

Abstract Rationale Leisure activities have wide-ranging benefits for physical and mental health. However, previous studies have often focused on “leisure” as a homogeneous group of activities. This study was therefore designed to take a prospective and comparative approach exploring different types of leisure activities, as well as investigating whether frequency of engagement is associated with strength of benefits. Method Data from the 1970 British Cohort Study Waves 9 (age 42) and 10 (age 46) were analysed (N = 5,639). Eight domains derived from the SF-36 health survey questionnaire were used to measure health functioning (general health, vitality, bodily pain, social functioning, physical functioning, mental health, role limitations due to emotional, and role limitations due to physical problems). Leisure activities included physical activity, culture engagement, arts participation, volunteering or community engagement, and literature activities. Both ordinary least squares and logistic regressions were applied. Results Physical activity was associated with greater levels of physical functioning, general health, and vitality at higher frequencies, while cultural engagement was associated with social functioning and physical functioning when engaged in several times a year. Arts participation and literature activities had a general negative association with health functioning. Engagements in volunteering/community groups showed varying associations with health functioning (both positive and negative) depending on the levels of engagements. Conclusion This research suggests that the types of leisure activities and levels of engagement can have differential associations with health amongst middle-aged adults. This may be helpful for public health initiatives and programmes such as social prescribing schemes when formulating programmes, especially regarding ‘dosage’ of engagement. Further, the overall benefits of high engagement frequency suggest that increasing leisure engagement could play an important role in supporting improving health and wellbeing at a population level.

Abstract The COVID-19 pandemic led to national lockdowns in countries around the world. Whilst lockdowns were shown to be effective in reducing the spread of disease, they were also associated with adverse effects on people’s mental health and wellbeing. Previous studies have suggested that time spent outside may have played a role in mitigating these negative effects, but research on this topic remains limited. Therefore, this study was designed to explore the longitudinal associations between going outdoors and people’s mental health and wellbeing during the first national lockdown (March–May 2020) in the UK. Data from 35,301 participants from the COVID-19 Social Study were analysed. Fixed effects regression was used to explore the longitudinal association between changes in going outdoors (the number of days spent outside) and changes in depressive symptoms, anxiety symptoms, life satisfaction and loneliness. A range of household and neighbourhood moderators were examined. Results show that an increase in the number of days spent outside was associated with decreases in depressive and anxiety symptoms and an increase in life satisfaction. Associations were more salient amongst people living with others, and those with greater satisfaction with their neighbourhood walkability and green spaces. No longitudinal association was found with loneliness. Overall, our analyses showed a positive association between going outdoors and improved mental health and wellbeing during the first COVID-19 lockdown in the UK. These findings are important for formulating guidance for people to stay well at home during pandemics and for the on-going nature-based social prescribing scheme.

BackgroundThere has been much research into the mental health impact of the Coronavirus Disease 2019 (COVID-19) pandemic and how it is related to time-invariant individual characteristics. However, there is still a lack of research showing long-term trajectories of mental health across different stages of the pandemic. And little is known regarding the longitudinal association of time-varying factors with mental health outcomes. This study aimed to provide a longitudinal profile of how mental health in adults changed across different stages of the COVID-19 pandemic and to examine their longitudinal associations with time-varying contextual (e.g., COVID-19 policy response and pandemic intensity) and individual level factors.Methods and findingsThis study used data from a large panel study of over 57,000 adults living in England, who were followed up regularly for 2 years between March 2020 and April 2022. Mental health outcomes were depressive and anxiety symptoms. Depressive symptoms were assessed by the Patient Health Questionnaire (PHQ-9) and anxiety symptoms by the Generalized Anxiety Disorder assessment (GAD-7). Entropy balancing weights were applied to restore sample representativeness. After weighting, approximately 50% of participants were female, 14% from ethnic minority backgrounds, with a mean age of 48 years. Descriptive analyses showed that mental health changes were largely in line with changes in COVID-19 policy response and pandemic intensity. Further, data were analysed using fixed-effects (FE) models, which controlled for all time-invariant confounders (observed or not). FE models were fitted separately across 3 stages of the COVID-19 pandemic, including the first national lockdown (21/03/2020-23/08/2020), second and third national lockdowns (21/09/2020-11/04/2021), and "freedom" period (12/04/2021-14/11/2021). We found that more stringent policy response (measured by stringency index) was associated with increased depressive symptoms, in particular, during lockdown periods (β = 0.23, 95% confidence interval (CI) = [0.18 to 0.28], p < 0.001; β = 0.30, 95% CI = [0.21 to 0.39], p < 0.001; β = 0.04, 95% CI = [-0.03 to 0.12], p = 0.262). Higher COVID-19 deaths were also associated with increased depressive symptoms, but this association weakened over time (β = 0.29, 95% CI = [0.25 to 0.32], p < 0.001; β = 0.09, 95% CI = [0.05 to 0.13], p < 0.001; β = -0.06, 95% CI = [-0.30 to 0.19], p = 0.655). Similar results were also found for anxiety symptoms, for example, stringency index (β = 0.17, 95% CI = [0.12 to 0.21], p < 0.001; β = 0.13, 95% CI = [0.06 to 0.21], p = 0.001; β = 0.10, 95% CI = [0.03 to 0.17], p = 0.005), COVID-19 deaths (β = 0.07, 95% CI = [0.04 to 0.10], p < 0.001; β = 0.04, 95% CI = [0.00 to 0.07], p = 0.03; β = 0.16, 95% CI = [-0.08 to 0.39], p = 0.192). Finally, there was also evidence for the longitudinal association of mental health with individual level factors, including confidence in government/healthcare/essentials, COVID-19 knowledge, COVID-19 stress, COVID-19 infection, and social support. However, it is worth noting that the magnitudes of these longitudinal associations were generally small. The main limitation of the study was its non-probability sample design.ConclusionsOur results provided empirical evidence on how changes in contextual and individual level factors were related to changes in depressive and anxiety symptoms. While some factors (e.g., confidence in healthcare, social support) clearly acted as consistent predictors of depressive and/or anxiety symptoms, other factors (e.g., stringency index, COVID-19 knowledge) were dependent on the specific situations occurring within society. This could provide important implications for policy making and for a better understanding of mental health of the general public during a national or global health crisis.

Abstract Many studies have investigated the impact of the COVID-19 pandemic on mental health. Throughout the pandemic, time spent at home increased to a great extent due to restrictive measures. Here we set out to investigate the relationship between housing conditions and the mental health of populations across European countries. We analyzed survey data collected during spring 2020 from 69,136 individuals from four cohorts from Denmark, France, and the UK. The investigated housing conditions included household density, composition, and crowding, access to outdoor facilities, dwelling type, and urbanicity. The outcomes were loneliness, anxiety, and life satisfaction. Logistic regression models were used, and results were pooled using random-effects meta-analysis. In the meta-analysis, living alone was associated with higher levels of loneliness (OR = 3.08, 95% CI 1.87–5.07), and lower life satisfaction (OR = 1.27, 95% CI 1.05–0.55), compared to living with others. Not having access to an outdoor space and household crowding were suggestively associated with worse outcomes. Living in crowded households, living alone, or lacking access to outdoor facilities may be particularly important in contributing to poor mental health during a lockdown. Addressing the observed fundamental issues related to housing conditions within society will likely have positive effects in reducing social inequalities, as well as improving preparedness for future pandemics.

Abstract Background There is increasing awareness of the importance of patient activation (knowledge, skills, and confidence for managing one’s health and health care) among clinicians and policy makers, with emerging evidence showing higher levels of patient activation are associated with better health outcomes and experiences of health care. This study aimed to examine the association between patient activation and a wide range of specific types of healthcare service utilisation in England, including GP and non-GP primary care, elective and emergency hospital admissions, outpatient visits, and attendances at the Accident and Emergency department. Methods Data were derived from linked electronic patient records collected by primary and secondary healthcare providers in North West London between January 2016 and November 2019. Our analyses focused on adults (18+) with a valid Patient Activation Measure (PAM). After excluding patients with missing data, we had an analytical sample of 15,877 patients. Data were analysed using negative binomial regression and logistic regression models depending on the outcome variable. Results Patients had a mean activation score of 55.1 and a standard deviation (SD) of 17.7 (range: 0–100). They had an average of 5.4 GP visits (SD = 8.0), 26.8 non-GP visits (SD = 23.4) and 6.0 outpatient attendances (SD = 7.9) within a one-year follow-up. About 24.7% patients had at least one elective admission, 24.2% had one or more emergency admissions, and 42.3% had one or more A&E attendance within the follow-up. After accounting for a number of demographic and health factors, we found a linear (or proximately linear) association between patient activation and the number of GP visits, emergency admissions and A&E attendance, but a non-linear relationship between patient activation and the number of non-GP visits, the number of outpatient attendance and elective inpatient admission. Conclusions This study has provided strong empirical evidence from England linking patient activation with healthcare service utilisation. It suggests the value of supporting patient activation as a potential pathway to ease the burden of healthcare system.

Abstract Recent studies have shown reduced physical activity at early stages of the COVID-19 pandemic. However, there is a lack of investigation on longitudinal changes in physical activity beyond lockdowns and stay-at-home orders. Moreover, it is unclear if there is heterogeneity in physical activity growth trajectories. This study aimed to explore longitudinal patterns of physical activity and factors associated with them. Data were from the UCL COVID-19 Social Study. The analytical sample consisted of 35,915 adults in England who were followed up for 22 weeks from 24th March to 23rd August 2020. Data were analysed using growth mixture models. Our analyses identified six classes of growth trajectories, including three stable classes showing little change over time (62.4% in total), two classes showing decreasing physical activity (28.6%), and one class showing increasing physical activity over time (9%). A range of factors were found to be associated the class membership of physical activity trajectories, such as age, gender, education, income, employment status, and health. There is substantial heterogeneity in longitudinal changes in physical activity during the COVID-19 pandemic. However, a substantial proportion of our sample showed persistent physical inactivity or decreasing physical activity. Given the well-established link between physical activity and health, persistent or increased physical inactivity is likely to have both immediate and long-term implications for people’s physical and mental health, as well as general wellbeing. More efforts are needed to promote physical activity during the pandemic and beyond.

This paper studies a method for high-precision acquisition of position signals for permanent magnet direct drive servo motors at low speed. First of all, the problem of poor position feedback accuracy and sensor feedback delay in the low-speed operation of the permanent magnet direct drive servo motor is analyzed. Secondly, through analysis and simulation, it is found that the interpolation method can play a certain role in compensating the rotor position signal. However, when the speed is close to 0, the output signal of the sensor will fluctuate in a short time, which will affect the speed control accuracy. Therefore, this paper uses the observer method to achieve high-precision acquisition of the position signal of the permanent magnet direct drive servo motor at low speed. The observer method adopts the idea of combining the system model and closed-loop control. Additionally, it makes full use of the parameter information of the motor system. The control performance of the motor can be better guaranteed through the design of the observer parameters and the accuracy of the rotor position estimation result has been greatly improved. Finally, an experimental platform for permanent magnet direct drive servo motors is built, and the rotor position signal acquisition method based on the observer method is verified to have good performance through simulation and experiments. Not only the accuracy of the rotor position estimation result is improved, but also the motor control performance is improved, realizing the stable operation of the permanent magnet direct drive servo motor at low speed.

Abstract Background Engaging in the arts is a health-related behavior that may be influenced by social inequalities. While it is generally accepted that there is a social gradient in traditional arts and cultural activities, such as attending classical music performances and museums, previous studies of arts engagement in the US have not adequately investigated whether similar demographic and socioeconomic factors are related to other forms of arts engagement. Methods Using cross-sectional data from the General Social Survey (GSS) in the US, we examined which demographic, socioeconomic, residential, and health factors were associated with attendance at arts events, participation in arts activities, membership of creative groups, and being interested in (but not attending) arts events. We combined data from 1993 to 2016 in four analytical samples with a sample size of 8684 for arts events, 4372 for arts activities, 4268 for creative groups, and 2061 for interested non-attendees. Data were analysed using logistic regression. Results More education was associated with increased levels of all types of arts engagement. Parental education demonstrated a similar association. Being female, compared to male, was also consistently associated with higher levels of engagement. Attendance at arts events was lower in participants with lower income and social class, poorer health, and those living in less urban areas. However, these factors were not associated with participation in arts activities or creative groups or being an interested non-attendee. Conclusions Overall, we found evidence for a social gradient in attendance at arts events, which was not as pronounced in participation in arts activities or creative groups or interest in arts events. Given the many benefits of engagement in the arts for education, health, and wider welfare, our findings demonstrate the importance of identifying factors to reduce barriers to participation in the arts across all groups in society.

This paper presents a novel direct power control (DPC) strategy based on an optimized sector division for a three-phase coupled inductor-based bipolar output active rectifier (TCIBAR) applied in more electric aircraft (MEA). First, based on the instantaneous power theory, the power model of the TCIBAR is built in the synchronous rotating coordinate system. Second, to implement the hysteresis power control of TCIBAR without causing the runaway of the zero-sequence current in the three-phase coupled inductor (TCI), a set of new voltage vectors that have the same zero-sequence voltage (ZSV) component are synthesized and adopted in the proposed DPC strategy. Third, by quantitatively analyzing the effect of the new synthesized voltage vectors on the power variation of TCIBAR, an optimized sector division method is proposed to improve the accuracy of power control and reduce the phase current harmonics in TCIBAR. Finally, to maintain the voltage balance of the bipolar dc ports in TCIBAR, voltage balance control is studied in the proposed DPC strategy. The proposed DPC strategy is researched on an experimental platform of TCIBAR, and the results show that the proposed DPC strategy is feasible and has good static and dynamic performance.

Direct power control (DPC) has gained increasing attention in recent years as a simple and efficient control strategy for pulse width modulation (PWM) rectifiers. In this paper, the idea of DPC is introduced into the three-phase coupled inductor-based bipolar-output active rectifier (TCIBAR) for the first time, and a virtual vector-based direct power control (VVB-DPC) strategy is proposed for TCIBAR to realize the bipolar DC power supply for more electric aircraft (MEA). First, the mathematical model of the TCIBAR is deduced, and the basic principle of the classic DPC strategy is reviewed. On this basis, the limitations of the classic DPC strategy in TCIBAR control are analyzed. Second, a set of virtual vectors are derived to establish a novel virtual-vector switching table. Based on the virtual-vector switching table, the hysteresis power control of TCIBAR can be realized without affecting the DC-side neutral-point potential of TCIBAR. Finally, a neutral-point potential control method based on DPC architecture is studied and integrated into the VVB-DPC strategy to maintain the bipolar DC voltage balance of TCIBAR under unbalanced load conditions. The VVB-DPC strategy is experimentally studied on a TCIBAR prototype, and the experimental results verify the feasibility and effectiveness of the proposed strategy.

The ±270 V bipolar dc distribution has become an attractive power supply scheme in more electric aircraft (MEA). In this paper, a dc voltage balancing strategy based on zero vector redistribution (ZVR) is proposed for a three-phase coupled inductor-based bipolar-output active rectifier (TCIBAR) to achieve balanced ±270 V power supply for MEAs. First, the mathematical model of the TCIBAR is developed in the rotating reference frame and the zero-sequence equivalent circuit of the three-phase coupled inductor (TCI) branch is derived. On this basis, the effect mechanism of the zero-sequence voltage is analyzed in balancing the output dc voltages of the TCIBAR. Second, a voltage balancing control scheme is designed to control the zero-sequence voltage and maintain the dc voltage balance of the TCIBAR under unbalanced load condition. Finally, a ZVR - space vector pulse width modulation (ZVR-SVPWM) method is proposed. With the ZVR-SVPWM method, the duration time of zero vectors can be redistributed to modulate the desired zero-sequence voltage for the TCIBAR. The proposed dc voltage balancing strategy for the TCIBAR is implemented on an experimental platform, and the experimental results verify the feasibility and effectiveness of the proposed control scheme and ZVR-SVPWM method.

Abstract Loneliness and social isolation have been identified as important predictors of various health outcomes, but little research has investigated their influence on falls. This study aimed to investigate the longitudinal association between loneliness, social isolation and falls amongst older adults in England, looking at both self-reported falls and falls that require hospital admissions. This study drew on large scale, nationally representative data from the English Longitudinal Study of Ageing linked with Hospital Episode Statistics. Data were analysed using survival analysis, with self-reported falls (total sample = 4013) and falls require hospital admission being modelled separately (total sample = 9285). There was a 5% increase in the hazard of self-reported falls relative to one point increase in loneliness independent of socio-demographic factors (HR: 1.05, 95% CI: 1.02–1.08), but the association was explained away by individual differences in health and life-style measures (HR: 1.03, 95% CI: 1.00–1.07). Both living alone (HR: 1.18, 95% CI: 1.07–1.32) and low social contact (HR: 1.04, 95% CI: 1.01–1.07) were associated with a greater hazard of self-reported falls even after controlling for socio-demographic, health and life-style differences. Similar results were also found for hospital admissions following a fall. Our findings were robust to a variety of model specifications.

Summary: Background: Smoking is often colloquially considered “social”. However, the actual relationship of smoking with current and future social isolation and loneliness is unclear. We therefore examined these relationships over a 12-year follow-up. Methods: In this cohort study, we used a nationally representative sample of community dwelling adults aged 50 years and over from the English Longitudinal Study of Ageing (N=8780) (45% male, mean(SD) age 67(10) years. We examined associations of self-reported smoking status at baseline assessment, with social isolation (low social contact, social disengagement, domestic isolation), and loneliness (3-item UCLA loneliness scale), measured at baseline, and follow-up at 4, 8 and 12 years, using ordinary least squares regression models. Findings: At baseline, smokers were more likely to be lonely (coef.=0·111, 95% CI 0·025 – 0·196) and socially isolated than non-smokers, having less frequent social interactions with family and friends (coef.= 0·297, 95%CI 0·148 – 0·446), less frequent engagement with community and cultural activities (coef.= 0·534, 95%CI 0·421 – 0·654), and being more likely to live alone (Odds Ratio =1·400, 95%CI 1·209 – 1·618). Smoking at baseline was associated with larger reductions in social contact (coef.=0·205, 95%CI 0·053 – 0·356, to 0·297, 95%CI 0·140 – 0·455), increases in social disengagement (coef.=0·168, 95%CI 0·066 – 0·270, to coef.=0·197, 95%CI 0·087 – 0·307), and increases in loneliness (coef.=0·105, 95%CI 0·003 – 0·207), at 4-year follow-up) over time. No association was found between smoking and changes in cohabitation status. Findings were independent of all identified confounders, including age, sex, social class and the presence of physical and mental health diagnoses. Interpretation: Smoking is associated with the development of increasing social isolation and loneliness in older adults, suggesting smoking is detrimental to aspects of psychosocial health. The idea that smoking might be prosocial appears a misconception. Funding: UK Economic and Social Research Council & Imperial College London.

Between March 2020 and March 2021, the United Kingdom (UK) experienced three lockdowns due to the COVID-19 pandemic. Given the evident association between arts engagement and wellbeing, this study was designed to compare the predictors and patterns of home-based arts engagement during these lockdowns. Data analysed in this study were from the UK COVID-19 Social Study run by University College London. Multinomial logistic regression was used to identify predictors of arts engagement and compare (i) respondents' engagement levels during the first lockdown in April/May 2020 and their levels in pre-pandemic times (N = 23,086), (ii) their engagement levels during the second lockdown in November/December 2020 with their levels during the first lockdown (N = 11,481), and (iii) their engagement levels during the third lockdown in January/February 2021 with their levels during the first lockdown (N = 13,270). During first lockdown, 1 in 4 increased their arts engagement and 1 in 6 decreased it. Of those who increased, 2 in 5 maintained or further increased their engagement in subsequent lockdowns, but just 7% of those who had decreased their engagement increased it. Younger adults (aged 18-29) showed initial increases in first lockdown, whilst people who were not employed and those with a physical health condition showed decreases and people with a mental health condition showed changes during the first lockdown (both increases and decreases). Females and people with higher education showed continuous changes across the three lockdowns, with women being more likely to increase their engagement and those with higher education being less likely to decrease. People of ethnic minorities and those with higher income declined their engagement in the third lockdown. This study provides insight into levels of arts engagement across the three national lockdowns in the UK and suggests that the pandemic may have affected long-term cultural behaviours for some groups.

Abstract A smart power flow node (SPFN) aimed at a hybrid ac/dc electric power system (EPS) for future more electric aircraft is presented. The SPFN is researched to enhance the performance of the EPS. Based on the SPFN, new power flow paths are established for the EPS, and intelligent power flow management of the EPS is realised. A multi‐port topology is designed for the SPFN to be compatible with different ac and dc power ports. Moreover, three operating modes of the SPFN are studied to realise uninterrupted power supply, power support of high‐power load and power transfer of the feedback energy from regenerative load. The experimental results verify the feasibility and availability of the SPFN and show that the SPFN can improve the equivalent capacity as well as the power supply reliability of the EPS.

Background: Cognitive impairment is common in older people admitted to hospital, but previous research has focused on single conditions. Objective: This project sits in phase 0/1 of the Medical Research Council Framework for the Development and Evaluation of Complex Interventions. It aims to develop an understanding of current health-care outcomes. This will be used in the future development of a multidomain intervention for people with confusion (dementia and cognitive impairment) in general hospitals. The research was conducted from January 2015 to June 2018 and used data from people admitted between 2012 and 2013. Design: For the review of outcomes, the systematic review identified peer-reviewed quantitative epidemiology measuring prevalence and associations with outcomes. Screening for duplication and relevance was followed by full-text review, quality assessment and a narrative review (141 papers). A survey sought opinion on the key outcomes for people with dementia and/or confusion and their carers in the acute hospital (n = 78). For the analysis of outcomes including cost, the prospective cohort study was in a medical admissions unit in an acute hospital in one Scottish health board covering 10% of the Scottish population. The participants (n = 6724) were older people (aged ≥ 65 years) with or without a cognitive spectrum disorder who were admitted as medical emergencies between January 2012 and December 2013 and who underwent a structured nurse assessment. ‘Cognitive spectrum disorder’ was defined as any combination of delirium, known dementia or an Abbreviated Mental Test score of

Background: In response to the COVID-19 pandemic, governments around the world instituted various public-health measures. Our project aimed to highlight the most significant similarities and differences in key mental-health indicators between four Western and Northern European countries, and identify the population subgroups with the poorest mental-health outcomes during the first months of the pandemic. Methods: We analysed time-series survey data of 205,084 individuals from seven studies from Denmark, France, the Netherlands, and the UK to assess the impact of the pandemic and associated lockdowns. All analyses focused on the initial lockdown phase (March–July 2020). The main outcomes were loneliness, anxiety, and COVID-19-related worries and precautionary behaviours. Findings: COVID-19-related worries were consistently high in each country but decreased during the gradual reopening phases. While only 7% of the respondents reported high levels of loneliness in the Netherlands, percentages were higher in the rest of the three countries (13–18%). In all four countries, younger individuals and individuals with a history of mental illness expressed the highest levels of loneliness. Interpretation: The pandemic and associated country lockdowns had a major impact on the mental health of populations, and certain subgroups should be closely followed to prevent negative long-term consequences. Younger individuals and individuals with a history of mental illness would benefit from tailored public-health interventions to prevent or counteract the negative effects of the pandemic. Individuals across Western and Northern Europe have thus far responded in psychologically similar ways despite differences in government approaches to the pandemic. Funding: See the Funding section.

There is widespread concern about the potential impact on health and social care services of the ageing population and long-term health conditions, such as dementia. To effectively plan services it is important to understand current need and use and identify gaps in provision. Using data from the Cognitive Function and Ageing Study Wales (CFAS Wales), we used logistic regression to model the relationship between health (self-rated health, cognitive impairment, and activities of daily living), and the use of health and care services. CFAS Wales is a longitudinal cohort study of people aged 65 years and over, in two areas in Wales, UK, over-sampling those aged 75 years and over. Participants (n = 3593) answered a wide range of health and lifestyle questions and completed a variety of cognitive and physical health assessments. Data from 3153 people from wave 1 and 1968 people from wave 2 were analysed.As anticipated we found poorer health, on some indicators, predicted greater service use, including social care, hospital, general practitioner, and nursing services. However, cognitive impairment did not predict greater service use, except for social care. Controlling for age, sex, socio-economic status, social connection indices and area environment, conversely we found lower reported uptake of allied health services by people with cognitive impairment. Further analysis showed that people with a cognitive impairment were less likely to report having a sight-check or seeing a dentist in the previous year, a finding replicated in wave 2. These differences were not explained by transportation issues. In contrast, we did not find a significant difference in reported uptake of hearing checks or physiotherapist use, with mixed evidence of differences in chiropodist visits. Not accessing these preventative services may not only exacerbate existing conditions but have further downstream negative consequences for health and well-being in people who are cognitively impaired.

IntroductionArts and cultural engagement are associated with a range of mental and physical health benefits, including promoting heathy aging and lower incidence of age-related disabilities such as slower cognitive decline and slower progression of frailty. This suggests arts engagement constitutes health-promoting behaviour in older age. However, there are no large-scale studies examining how the predictors of arts engagement vary with age.MethodsData from the Health and Retirement Study (2014) were used to identify sociodemographic, life satisfaction, social, and arts appreciation predictors of (1) frequency of arts engagement, (2) cultural attendance, (3) difficulty participating in the arts, and (4) being an interested non-attendee of cultural events. Logistic regression models were stratified by age groups [50-59, 60-69, ≥70] for the frequency of arts participation outcome and [50-69 vs ≥70] all other outcomes.ResultsFindings indicated a number of age-related predictors of frequent arts engagement, including gender, educational attainment, wealth, dissatisfaction with aging, and instrumental activities of daily living (iADL). For cultural event attendance, lower interest in the arts predicted lack of engagement across age groups, whereas higher educational attainment and more frequent religious service attendance became predictors in older age groups (≥ 70). Adults in both age groups were less likely to report difficulties engaging in the arts if they had lower neighbourhood safety, whilst poor self-rated health and low arts appreciation also predicted reduced likelihood of this outcome, but only in the younger (50-69) age group. Adults in the older (≥ 70) age group were more likely to be interested non-attendees of cultural events if they had higher educational attainment and less likely if they lived in neighbourhoods with low levels of safety.ConclusionsOur results suggest that certain factors become stronger predictors of arts and cultural engagement and barriers to engagement as people age. Further, there appear to be socioeconomic inequalities in engagement that may increase in older ages, with arts activities overall more accessible as individuals age compared to cultural engagement due to additional financial barriers and transportation barriers. Ensuring that these activities are accessible to people of all ages will allow older adults to benefit from the range of health outcomes gained from arts and cultural engagement.

The Xin'an Medical School began in the Jin Dynasty (266–420), developed in the Song Dynasty (960–1279), prospered in the Ming and Qing dynasties (1368–1911), and has been passed down to the modern era. As a school of medicine with distinct regional characteristics, it has contributed to the development of traditional Chinese medicine and exerted far-reaching influence, mainly in literature resources, medical theory, clinical application, and spiritual culture. This paper intends to discuss its academic characteristics and contribution to the development of traditional Chinese medicine, focusing on its formation, academic inheritance and innovation, overseas popularization, and integration of Confucianism, Taoism, and Buddhism in medicine. Keywords: Xin'an Medical School, Regional medical schools, Ancient Huizhou, Achievements and characteristics

To solve the problem of severe DC bus voltage fluctuations caused by frequent changes in the distributed electric propulsion aircraft load, and to further optimize the size and life of the hybrid energy storage system (HESS), this paper proposes a method based on three-step power distribution (TSPD). This strategy realizes the reasonable distribution of battery and supercapacitor power by using a low pass filter. Through the introduction of a supercapacitor state-of-charge (SOC) automatic recovery control and maximum power value dynamic limit strategy, the size of the HESS is optimized, and the service life of the energy storage device is extended. Finally, simulation and experiment platform are built to prove the effectiveness of the proposed strategy.

This paper presents a thrust cooperative control strategy of multiple propulsion motors for distributed electric propulsion aircraft. The control strategy can keep the propulsion motors running synchronously when the aircraft is flying in a straight line; at the same time, when the aircraft needs to turn, the yaw moment is generated by changing the speed of the propulsion motors on both sides, so as to achieve the given yaw angle of the aircraft. In order to verify the control strategy, the paper also carries out simulation and experimental verification, and the results show that the cooperative control strategy is feasible.

Objective: To explore the recent 20 years' herbal administration rules in TCM treatments of ovarian cysts (OCs) based on data mining. Methods: A prescription database for ovarian cysts was established by ACCESS 2007. Importing the database into SPSS17.0 and SPSS Modeler14.1. SPSS17.0 was used for descriptive and cluster analyses, while SPSS Modeler14.1 was used for association rules analysis. Results: After screening, 363 prescriptions were obtained. The 10 most frequently-used Chinese herbal medicines are Zedoaria (Rhizoma Curcumae), Poria cocos (Poria), Common buried rubber (Rhizoma Sparganii), Red peony root (Radix Paeoniae Rubra), Peach seed (Semen Persicae), Danggui (Radix Angelicae Sinensis), Chinese angelica (Ramulus Cinnamomi), Liquorice root (Radix Glycyrrhizae), Pangolin scales (Squama Manis) and Moutan cortex (Cortex Moutan Radicis); the 5 most common syndromes of OCs are qi stagnation and blood stasis, phlegm and blood stasis, uterine blood stasis, stagnation of liver qi and retention of phlegm and dampness, nearly to 54.26%; In association rules analysis, 5 sets of two-herbs association rules were obtained, 17 sets of three-herbs association rules were obtained, 22 sets of four-herbs association rules were obtained and 4 sets of five-herbs association rules were obtained; By clustering, 13 sets of core couplet medicinals were obtained. Conclusion: Medicinal herbs for promoting blood circulation to remove blood stasis, resolve hard lumps, for strengthening the spleen, eliminating phlegm, and relieving liver qi stagnation were highly used in the treatment of OCs; Herbs attributed to the Liver Meridian, the Spleen Meridian and the Heart Meridian were highly used in OCs; The compatibility of herbs for promoting blood circulation to remove blood stasis and resolve hard lumps were highly used; Guizhi Fuling Wan (GFW) was often used and combined with other herbs in the treatment of OCs.

There is growing evidence for the impact of arts engagement on later life cognition. However, confounding by socioeconomic factors may have led to an overestimation of this association. We analyzed data from 4,344 older adults in the Wisconsin Longitudinal Study. We measured participatory (e.g. painting, making music, crafts) and receptive (e.g. concert, play, museum) arts engagement separately. Participants completed six neurocognitive tests measuring two distinct domains of cognitive function (episodic/working memory and executive function/language) concurrently and seven years later. We used inverse probability of treatment weighting (IPTW) to remove confounding by a range of demographic and socioeconomic factors. Engaging in participatory or receptive arts for up to one hour per week (but not more frequently) was associated with better subsequent executive function/language. Similarly, engaging in receptive arts activities for up to three hours per week (but not more frequently) was associated with better subsequent episodic/working memory. These effects were of similar sizes to doing vigorous physical activity for up to one hour per week. However, our findings also highlight key methodological issues when exploring the relationship between arts engagement and cognition that should be considered in future studies, including measurement bias, life-course stage, length of follow-up, variation in outcomes, attrition, and missing data.

A novel primary consequent-pole tubular transverse-flux flux-reversal linear machine (TTFFRLM) is proposed in this paper. The permanent magnets (PMs) of the machine are located on the inner surface of the short teeth of the primary iron cores for reducing the amount of PM in long stroke drive systems, and the primary is easily manufactured. The structure and principle of this machine are analyzed in detail. Based on the unit machine, a no-load equivalent magnetic circuit model is established by using the magnetic circuit method. Then, the equations of the no-load back electromotive force (back-EMF) and the electromagnetic thrust force are deduced. The simulation models of the unit machine are established by equivalent 2D finite element method (FEM) for saving computation time, and the static characteristics, including the flux field, the no-load back-EMF, and the electromagnetic thrust force, are analyzed. Detailed simulation and experimental results of a three-phase 4-poles 12-slots machine are given. The results verify the correctness and effectiveness of topology, model, and analysis method of the proposed TTFFRLM. Compared with the conventional TTFFRLM, the proposed prototype has the advantages of a lower cost and smaller electromagnetic thrust force ripple.

In order to broaden the limited utilization range of wind power and improve the charging and discharging control performance of the storage battery in traditional small wind power generation systems, a wind power system based on a vertical-axis off-grid induction generator is proposed in this paper. The induction generator not only can run in a wide wind speed range but can also assist the vertical-axis wind turbine to realize self-starting at low wind speed. Combined with the maximum power point tracking method, the slip frequency control strategy is employed to regulate the pulse width modulation (PWM) converter to control the output power of the proposed system when the wind speed and load change. The charge and discharge of the storage battery is realized by the segmented current-limiting control strategy by means of an electric power unloader device connected to the DC bus. All these implement a balanced and stable operation of the proposed power generation system. The experimental research on the 5.5 kW prototype system is developed, and the corresponding results verify the correctness and feasibility of the system design and control strategy. Some comparison experiments with a magnetic suspension permanent magnet synchronous generator (PMSG) demonstrate the application prospect of the proposed vertical-axis off-grid induction generator wind power system.

Rising hospital admissions due to respiratory disease (RD) are a major challenge to hospitals. This study explored modifiable social risk factors among 4478 older adults from the English Longitudinal Study of Ageing. Data were linked with administrative hospital records and mortality registry data (follow-up 9.6 years) and analysed using survival analysis accounting for competing risks. Living alone and social disengagement but not social contact or loneliness were associated with an increased risk of RD admissions, independent of socio-demographic, health and behaviour factors. Providing support for disengaged adults living alone who are at risk of RD admissions should be explored. [ABSTRACT FROM AUTHOR]

This paper presents a wide-speed-range-operation dual stator-winding induction generator (DWIG) dc generating system for wind power applications. In this system, the dc bus on the control-winding side and the dc bus on the power-winding side are connected in parallel to further widen the speed range of the constant dc voltage output, especially at low speeds. Based on the control mechanism of the DWIG and the instantaneous power theory, a control-winding-flux-orientation control strategy is employed. In order to improve the wind energy conversion efficiency at low wind speeds, the generator efficiency optimization method is investigated. The experimental results from a 20 kW/600 V prototype show that the proposed generating system can output the constant dc voltage in a speed range of 1:4, and the generator efficiency in the low speed range is improved, which both bring the advantages for wind power applications, such as expanding the scope of the wind energy utilization and capturing much more wind energy. [ABSTRACT FROM AUTHOR]

This paper presents the control strategy and dynamic performance of the dual stator-winding induction generator variable frequency ac (VFAC) generating system with inductive and capacitive loads. In this generating system, the power winding produces the VFAC electricity to feed loads, and the control winding is connected to a static excitation converter to keep the output voltage stable. Based on the change law of the reactive power provided by the control winding, an improved instantaneous slip frequency control (IISFC) strategy both with the load active and reactive power feedforward is proposed to improve the system dynamic performance. The information of the load active and reactive power is employed through two feedforward loops to rapidly change the reactive power provided by the control winding, so as to quicken the regulation of the slip frequency and excitation reactive power. The simulations and experimental results show that the system using the IISFC strategy has a good dynamic performance with inductive and capacitive loads, and demonstrate the correctness and validity of the proposed control strategy. [ABSTRACT FROM AUTHOR]

This paper presents the control and implementation of the dual-stator-winding induction generator for variable frequency AC (VFAC) generating system. This generator has two sets of stator windings embedded into the stator slots. The power winding produces the VFAC power to feed the loads, and the control winding is connected to the static excitation controller to control the generator for output voltage regulation with speed and load variations. On the basis of the idea of power balance, an instantaneous slip frequency control (ISFC) strategy using the information of both the output voltage and the output power is used in this system. A series of experiments is carried out on a 15 kW prototype for verification. Results show that the system has good static and dynamic performance in a wide speed range, which demonstrates that the ISFC strategy is suitable for this system. [ABSTRACT FROM AUTHOR]

This letter proposes a variable frequency ac (VFAC) stand-alone power system based on the dual stator-winding induction generator (DWIG) with the static excitation controller (SEC). A slip frequency control strategy using the information of the output voltage and the output power is employed to guarantee that the system has a desirable static and dynamic performance in a wide speed range. The experimental results on a prototype verify the principle and performance of the proposed control method. [ABSTRACT FROM AUTHOR]

A virtual Hall method for sensorless control of interior permanent magnet synchronous motors (IPMSMs) using high-frequency signal injection is presented. Based on the idea of virtual Hall, the position signal is easily estimated by comparing the magnitudes of three-phase inductances. The experimental results prove that the proposed method has good heavy-load operation capability with a brief control structure. [ABSTRACT FROM AUTHOR]