Agrobacterium sp. LAD9 capable of heterotrophic-aerobic nitrogen removal was applied into a single biological aerated filter (BAF) for bioaugmented treatment of municipal wastewater. The achievement of simultaneous nitrogen and carbon removal in the bioaugmented system was systematically evaluated by ratios of COD to nitrogen (COD/N), ranging from 1 to 20. The results showed that at an appropriate COD/N ratio of 10, the BAF exhibited excellent carbon and nutrients removal, the averaged removal efficiencies for COD, NH4+-N and TN were 92.3%, 100% and 80.0%, respectively. Long-term operation of the bioaugmented system also confirmed the stability of the treatment efficiency. Further comparisons of SOUR and PCR-DGGE profiles between the bioaugmented and the control system revealed that the introduction of strain LAD9 greatly changed the structure of original microbial community and facilitated their capabilities of aerobic nutrients removal. The proposed bioaugmentation strategy is of particular importance to upgrading or retrofitting concurrent municipal wastewater treatment systems. [GRAPHICS] .
Background Disabilities caused by perinatal asphyxia will burden child health and well-being. To date, our understanding about the situation and risk factors of perinatal asphyxia-induced disabilities among Chinese children is still limited. Objectives To evaluate the prevalence and socio-demographic risk factors of disabilities caused by perinatal asphyxia among Chinese children in 2006 and compare disability trajectories across different socio-demographic status. Methods Cross-sectional data came from the 2006 China National Survey on Disability which includes a total of 616,940 children aged 0– 17 years old was employed in the investigation. Perinatal asphyxia-induced disabilities were identified by following the guidance in consensus manuals. Population-weighted numbers and prevalence rates were investigated, and multivariable logistic regression was performed to evaluate associations between disabilities and socio-demographic factors. Adjusted predictions at representative values were computed to compare the disability trajectories relative to significant socio-demographic variables. Results The prevalence rate of disabilities caused by perinatal asphyxia was 7.70 per 10,000 children (95% CI: 7.01– 8.39). Male (OR 1.81, 95% CI: 1.47– 2.23) and low family income (OR: 1.73, 95% CI: 1.21– 2.49) have higher and the increase of per additional year of age (OR: 0.89, 95% CI: 0.88– 0.91) has lower probability of being disabilities caused by perinatal asphyxia. Further disability trajectories showed that differences in probability between gender and family income group were more evident before age 7 and weakened with increasing age. Conclusions Our results showed that both demographic and socioeconomic characteristics are risk factors for disabilities caused by perinatal asphyxia. Of these, gender and family income have much higher impact than other factors on the prevalence rate of disabilities caused by perinatal asphyxia at infants and young children. Multiple society sectors should increase their effort to bring about fundamental social change to prevent disabilities caused by perinatal asphyxia, especially concerning younger children and their families.
This work presents an ultra-low-power software-defined always-on wake-up system to drastically decrease the system power of Internet of Things (IoTs) devices, which usually operate in random-sparse-event (RSE) scenarios. It mainly thanks to a clock-free time-shielding level-crossing ADC (TS-LCADC), software-defined clock-free multi-function detectors, and an asynchronous pipelined event-driven architecture. First, by quantifying RSE noisy signals with clock-free adaptive sampling in a signal-noise-rejecting manner, the proposed TS-LCADC reduces number of sampling points and power, and consumes only 41 nW when on-call waiting for IoT events. Second, the proposed clock-free multi-function detectors with offline and online programmability are able to character the signal features of versatile IoTs events and allow versatile and dynamic wake-up functions. Third, the proposed asynchronous pipelined event-driven architecture minimizes the system activity and thus power, because a power-hungry high-performance system (HPS) is only woken up when a detected parameter crosses its corresponding threshold. As such, the long-term average power (LTA-power) is dominated by the always-on circuits in RSE scenarios. The measurement results achieve 71–75 nW for three typical applications, i.e., heart rate, epilepsy, and keyword envelope detection. The LTA power is only 57 nW when waiting for RSE events, which is 30 $\times $ lower than a prior general-purpose wake-up chip. Compared with other works of dedicated voice and acoustic wake-up functions, this work consumes 2 $\times $ and 17 $\times $ less power, respectively, while featuring 16 $\times $ higher signal bandwidth and a broader versatility.
Corporate environmental responsibility (CER) is increasingly gaining interest among researchers and practitioners. Despite this extensive interest, systematic research regarding the effect of sales on environmental performance remains scarce. In this study, an empirical analysis on a sample of 909 Chinese listed companies from 2010 to 2016 showed that sales positively impact environmental performance. This study also showed that corporate innovation mediates the relationship between sales and environmental performance. Furthermore, this study showed that environmental performance has a positive spatial spillover effect. Enterprises appear to promote their own environmental performance as a response to a rise in the environmental performance of their neighbors. The external control theory of organization has important reference significance and explanatory power for CER behavior in emerging economies.
Traditional studies of firm performance typically focus on the effect of market structure and rarely consider the impact of the spatiotemporal context in industrial competition.Using a sample of 1,555 listed companies from 2015 to 2018 in China, this study shows that the profit center of gravity tends to move from southeast to northwest, and that there are negative effects on firm performance with distance from the profit center of gravity. Moreover, when controlling for organizational variables, strategic interaction at the local level significantly mediates the relationship between spatiotemporal context at the global level and firm performance at the microlevel. This investigation provides preliminary support for strategic interaction as a significant mediator between spatiotemporal context and firm performance, and further highlights the relevance of spatiotemporal context and strategic interaction in determining firm performance. The results of this study contribute to our understanding of the dynamic mechanism of spatiotemporal context affecting firm performance and the role of strategic interaction at the local level in this relationship, which can improve the existing insights into new economic geography.
Danjiangkou Reservoir is the biggest artificial reservoir in China. But spatiotemporal distribution and risks of metal(loid)s in it were still unclear after the operation of Middle Route of South-to-North Water Diversion Project. In this study, distribution pattern of fifteen metal(loid)s in the Danjiangkou Reservoir was investigated. It was shown that metal(loid)s concentrations in the water were much lower than the drinking water quality standards in China, while Sb, Co, Cd and Cr were identified as the major pollutants in the sediments. Environment-metal(loid)s correlation analysis revealed total organic carbon, sulfate, temperature, dissolved oxygen and total phosphorus markedly controlled metal(loid)s distribution in the water, while organic carbon, total phosphorus and ammonia nitrogen shaped their distribution in the sediments. Results of risk assessment further revealed that the sediments of Danjiangkou Reservoir were minor to moderate polluted, and Sb, Cd exhibited the highest potential ecological risk. Additionally, source identification showed agricultural activities (25.3%), industrial and mining activities (17.5%) and natural processes (57.2%) were the dominant sources of metal(loid)s burden in the sediments. Overall, the results are of significance to understanding the ecological risk and pollution sources in the Danjiangkou Reservoir, which is essential for the effective management of metal(loid)s pollution.
Objective: As elderly parents today will share a longer life with their children than ever before, the spillover effects of children's human capital on parents' wellbeing become increasingly important. This study investigated whether children's schooling leads parents to give up smoking and whether the effects were moderated by their education or child-parent contact frequency. Methods: Using data from the China Health and Retirement Longitudinal Study (CHARLS), we conducted an instrumental variable analysis using China's compulsory schooling reform in the 1980s as a natural experiment. Results: The Instrumental Variable (IV) estimates suggest that elderly parents of more highly educated children are more likely to quit smoking. Moreover, the effects are more significant among parents who had not finished primary school and also slightly stronger among parents who live close to their children or meet their children frequently. Discussion: Our findings add to current evidence on spillover effects of education in smoking cessation. A child's education may exert the impact through the spillover of health knowledge.