The responding mechanism of indigenous bacteria in municipal wastewater inoculated with different concentrations of exogenous microalgae.

Indigenous bacteria popularly exist in real wastewater. Therefore, the potential interaction between bacteria and microalgae is inevitable in microalgae-based wastewater treatment systems. It is likely to affect the performance of systems. Accordingly, the characteristics of indigenous bacteria is worth serious concerning. Here we investigated the response of indigenous bacterial communities to variant inoculum concentrations of Chlorococcum sp. GD in municipal wastewater treatment systems. The removal efficiency of COD, ammonium and total phosphorus were 92.50%-95.55%, 98.00%-98.69%, and 67.80%-84.72%, respectively. The bacterial community responded differently to different microalgal inoculum concentrations, which was mainly affected by microalgal number, ammonium and nitrate. Besides, there were differential co-occurrence patterns and carbon and nitrogen metabolic function of indigenous bacterial communities. All these results indicated that bacterial communities responded significantly to environmental changes caused by the change of microalgal inoculum concentrations. The response of bacterial communities to different microalgal inoculum concentrations was beneficial for forming a stable symbiotic community of both microalgae and bacteria to remove pollutants in wastewater.

Exposure, perceived risk, and psychological distress among general population during the COVID-19 lockdown in Wuhan, China.

Introduction: The COVID-19 pandemic that has been going on since the end of 2019 impacts people on both the physical and psychological levels. However, the psychological status, especially its underlying psychosocial mechanisms among the general population in Wuhan, the earliest epicenter and hardest-hit city in China during the pandemic, has not been well investigated. This study aimed to examine the relationships between exposures, perceived risk, and psychological distress among the general population in Wuhan during the COVID-19 lockdown. Methods: Data were from a cross-sectional online survey conducted from 20 February to 4 March 2020. Final analyses included 4,234 Wuhan respondents. A 5-item Hopkins Symptom Checklist was adopted to assess respondents' psychological distress. Results: It was found that nervousness, fear, and worry were the most common symptoms among Wuhan residents during the lockdown. Exposure within a close physical distance, exposure within the social network, and perceived risk are significantly positively related to respondents' psychological distress. Moreover, perceived risk mediated the effects of exposures on respondents' psychological condition. Discussion: These findings conduce to identify the populations at higher risk of suffering psychological disturbance during the pandemic and are expected to inform the policymakers and mental health professionals to monitor and improve the perception of risk among the target population by appropriate interventions.

Who would rescue the dilemma of Chinese elderly care? An evolutionary game analysis and simulation research on the formalization of the domestic service industry with subsidy policy.

Since China entered the aging society, the surging demand for elderly care and the industrial upgrading of "silver economy" has forced the domestic service industry to face endogenous challenges. Among them, the formalization of the domestic service industry can effectively reduce the transaction costs and risks of actors, innovate the endogenous vitality of the industry, and promote the improvement of elderly care quality through a triangular employment relationship. By constructing a tripartite asymmetric evolutionary game model of clients, domestic enterprises and governmental departments, this study uses the stability theorem of differential equations to explore the influencing factors and action paths of the system's evolutionary stable strategies (ESS), and uses the research data collected from China to assign values to models for simulation analysis. This study finds that the ratio of the initial ideal strategy, the difference between profits and costs, subsidies to clients, and subsidies or punishments for breach of contract to domestic enterprises are the key factors affecting the formalization of the domestic service industry. Subsidy policy programs can be divided into long-term and periodic programs, and there are differences in the influence paths and effects of the key factors in different situations. Increasing domestic enterprises' market share with employee management systems, formulating subsidy programs for clients, and setting up evaluation and supervision mechanisms are efficient ways through which to promote the formalization of the domestic service industry in China. Subsidy policy of governmental departments should focus on improving the professional skills and quality of elderly care domestic workers, and also encourage domestic enterprises with employee management systems at the same time, to expand the scope of service beneficiaries by running nutrition restaurants in communities, cooperating with elderly care institutions, etc.

Amelioration and deterioration: Social network typologies and mental health among female domestic workers in China.

Previous quantitative studies on the effects of social network types on mental health have obtained inconsistent or conflicting results, due to problems such as sample selection bias or crude measurement of variables. In this study, we avoided these problems by using appropriate statistical methodology to examine the effect of various forms of social network on the mental health of a sample of 987 Chinese female domestic workers. Thus, we measured social network types in terms of both network attributes (friend networks and family networks) and interaction channels (face-to-face, telephone, and WeChat/QQ channels, where the latter are two popular online messaging platforms in China), and used the coarsened exact matching method to obtain a balanced sample. The results showed that social network typologies had positive and negative effects on the mental health of this sample of domestic workers, as evidenced by (1) In terms of network attributes, family networks were associated with improved mental health and friend networks were associated with worsened mental health; (2) In terms of interaction channels, the significant amelioration in mental health from family networks came from face-to-face interactions, the significant deterioration in mental health from friends networks came from telephone interactions, and in terms of other interaction channels, family networks and friends networks had no significant effect on mental health. Robustness tests indicated that these conclusions are reliable. We discuss the possible mechanisms of which different types of social networks influence mental health.

The Influence of Person-Job Fit on Health Status and Depression Among Chinese Domestic Workers: Mediating Effect of the Employer-Employee Relationship.

Domestic workers usually perform manual work in households. Unlike fixed work, their work tends to be individualized and atomized. Their person-job fit and relationship with employers might exert some influence on their health, both physical and psychological. This quantitative study explores the association between person-job fit, health status, and depressive symptoms among Chinese domestic workers by identifying the employer-employee relationship as a mediator. Data is collected from a survey of Chinese domestic workers conducted in four cities of Nanjing, Wuxi, Guangzhou, and Foshan (N = 1,003) in 2019. We test our theoretical model by conducting structural equation modeling. The results show that demand-ability fit is indirectly related to heath status and depressive symptoms via the employer-employee relationship. Need-supply fit is significantly associated with health status and depressive symptoms both directly (70% for health status and 72% for depressive symptoms, separately) and indirectly, via the mediating effect of the employer-employee relationship (30% for health and 28% for depressive symptoms, separately). Our findings suggest that appropriate policy and vocational training should be implemented to improve the health status of Chinese domestic workers.

Examining the impact of functional disability and cognitive impairment on mental health of Chinese elderly.

Depression and anxiety, as the two most prevalent psychiatric disorders, pose a huge challenge to the quality of life of the elderly. Using a sample of 7,721 elderly from the latest Chinese Longitudinal Health and Longevity Survey (CLHLS), the present study intended to explore the association between mental health and socioeconomic status, physical functional disability, and cognitive impairment among Chinese elderly by adopting multivariate logistic regression analyses. The results revealed that depression, anxiety, and their comorbidity are significantly higher in the elderly with instrumental activities of daily living (IADL) disability, cognitive impairment, financial strain, and living alone. Findings of the study will provide implications for policymakers, social workers, and individual caregivers to develop necessary intervention measures to improve the mental health of the elderly and promote successful aging.

Act Tough and Soft: Video Monitoring, Hongbao Gifts, and the Job Satisfaction of Domestic Workers.

There is a rapidly growing demand for domestic services among urban families in China. However, domestic work remains a low-status occupation with a high turnover rate. Focusing on the job satisfaction of domestic workers is useful to interpret this phenomenon. We investigate how the job satisfaction of domestic workers in China is affected by to two distinct labor control strategies used by their employers: the installation of video-monitoring devices in employers' homes (a "tough" control strategy), and the Chinese custom of giving monetary gifts, or "hongbao" (a "soft" control strategy). By analyzing data from surveys of domestic workers in four cities in China (N = 699), we find that video monitoring in employers' homes negatively impacts domestic workers' job satisfaction, and that hongbao gifts from employers significantly promote domestic workers' job satisfaction. The analysis of the causal mechanism based on a structural equation model suggests that video monitoring can increase the discrimination that domestic workers perceive, which in turn reduces their job satisfaction. In particular, we find that domestic workers' perception of discrimination completely mediates the effect of video monitoring on their job satisfaction. However, we also find that hongbao gifts significantly reduce domestic workers' perceptions of discrimination, and thus promote their job satisfaction; that is, the relationship between hongbao gifts and job satisfaction is partially mediated by discrimination. Our study provides a more comprehensive understanding of Chinese employers' labor control strategies and their effects on the job satisfaction of domestic workers.

Occupational Characteristics in the Outbreak of the COVID-19 Delta Variant in Nanjing, China: Rethinking the Occupational Health and Safety Vulnerability of Essential Workers.

The risk of contracting COVID-19 varies by occupation. Clarifying the occupational disparity in the infection risk is crucial to the prevention and control of the epidemic in the workplace. In late July, some new cases of COVID-19 were confirmed among cleaners working in Lukou International Airport in Nanjing, China. The infected cases rapidly increased and spread to many domestic cities in the following days. The present study traces the brief reports of epidemiological investigations among the confirmed cases released by the Nanjing government from 20 July to 2 August, and offers a descriptive analysis on the occupational distribution of these cases. Cleaners and other staff working in the airport were found to make up more than 40% of all cases. The overwhelming majority of the cleaner cases were confirmed in the first 7 days. The present study statistically ascertains that the airport cleaners were the initial sufferers and transmitters in this outbreak. They experienced occupational health and safety vulnerability on both individual and contextual levels, including workplace hazards, workplace safety policies, and lack of awareness and empowerment. Effective protection for essential workers and the strict surveillance of occupational health in the workplace is urgently needed.

Prediction of Epidemic Spread of the 2019 Novel Coronavirus Driven by Spring Festival Transportation in China: A Population-Based Study.

After the 2019 novel coronavirus (2019-nCoV) outbreak, we estimated the distribution and scale of more than 5 million migrants residing in Wuhan after they returned to their hometown communities in Hubei Province or other provinces at the end of 2019 by using the data from the 2013-2018 China Migrants Dynamic Survey (CMDS). We found that the distribution of Wuhan's migrants is centred in Hubei Province (approximately 75%) at a provincial level, gradually decreasing in the surrounding provinces in layers, with obvious spatial characteristics of circle layers and echelons. The scale of Wuhan's migrants, whose origins in Hubei Province give rise to a gradient reduction from east to west within the province, and account for 66% of Wuhan's total migrants, are from the surrounding prefectural-level cities of Wuhan. The distribution comprises 94 districts and counties in Hubei Province, and the cumulative percentage of the top 30 districts and counties exceeds 80%. Wuhan's migrants have a large proportion of middle-aged and high-risk individuals. Their social characteristics include nuclear family migration (84%), migration with families of 3-4 members (71%), a rural household registration (85%), and working or doing business (84%) as the main reason for migration. Using a quasi-experimental analysis framework, we found that the size of Wuhan's migrants was highly correlated with the daily number of confirmed cases. Furthermore, we compared the epidemic situation in different regions and found that the number of confirmed cases in some provinces and cities in Hubei Province may be underestimated, while the epidemic situation in some regions has increased rapidly. The results are conducive to monitoring the epidemic prevention and control in various regions.