Effect of gradual-increasing aeration mode in an aerobic tank on nutrients' removal and functional microbial communities.

Different aeration rates and modes in an aerobic tank of an anaerobic/anoxic/aerobic (A2O) process were investigated to reveal their influence on nitrogen and phosphorus removal efficiency. Meanwhile, Illumina high-throughput sequencing of partial 16S rRNA gene of bacteria was conducted to monitor the abundance and composition of microbial communities. The results showed that higher aeration rate led to better nutrients' removal efficiency. The gradual-increasing aeration mode along the wastewater stream enhanced the contaminants' removal and the system achieved chemical oxygen demand, [Formula: see text]-N, total nitrogen (TN) removal rates of 72%, 96% and 51%, respectively. However, the gradual-decreasing or uniform aeration modes resulted in inefficient removal of TN, especially the ammonia due to low DO in the end parts of A2O. Microbial community analysis indicated that denitrifying phosphorus-accumulating bacteria Acinetobacter spp. were the most dominant groups under the gradual-increasing aeration mode in all tanks of the A2O bioreactor. Moreover, the members of genera Clostridium, Thauera and Dechloromonas also largely existed in the system. The gradual-increasing aeration mode and cooperation of different groups of bacteria made the system stable and high-performance.

[Characteristics of nitrogen and phosphorus removal and control of membrane fouling in MBR and SMBR].

To improve the efficiency and running stability of wastewater advanced treatment, a sequencing membrane bioreactor (SMBR) and a traditional membrane bioreactor (MBR) were used to investigate the characteristics of nitrogen and phosphorus removal, and the effect of anoxic time on treatment systems and membrane fouling. Simultaneously, molecular biology techniques were applied to analyze the composition of microbial community and the structure of suspended sludge. The results showed that SMBR had higher efficiency in removing TN than MBR, which indicated that intermittent aeration could enhance the ability of nitrogen removal. SMBR and MBR had a similar removal efficiency of NH4(+)-N, TP, COD, and turbidity with the removal rates of 94%, 78%, 80%, and 97%, respectively. Extension of SMBR anoxic time had no effect on COD, NH4(+) -N removal but decreased TN and TP removal rate, dropping from 61% and 74% to 46% and 52%, respectively. Intermittent aeration and powder activated carbon (PAC) could both mitigate membrane fouling. The analysis on microbial community indicated that there was no difference in the composition and structure of microbial community between SMBR and MBR. Nitrospira and Dechloromonas were both highly abundant functional groups, which provided the basis for highly efficient control of bioreactors.

Qigong improves quality of life in women undergoing radiotherapy for breast cancer: results of a randomized controlled trial.

BACKGROUND: Radiotherapy may lead to side effects that undermine patients' quality of life (QOL). Although mind-body practices like qigong appear to improve QOL in cancer survivors, little is known about their benefits for patients who are receiving radiotherapy. Thus, in the current randomized controlled trial, the authors examined the efficacy of a qigong intervention on QOL in women with breast cancer during and after treatment. METHODS: Ninety-six women with breast cancer were recruited from a cancer center in Shanghai, China, and were randomized to a qigong group (N = 49) or a waitlist control group (N = 47). Women in the qigong group attended 5 weekly classes over 5 or 6 weeks of radiotherapy. QOL outcomes (ie, depressive symptoms, fatigue, sleep disturbance, and overall QOL) and cortisol slopes were assessed at baseline, during treatment, at the end of treatment, 1 month later, and 3 months later. RESULTS: The mean age of the women was 46 years (range, 25-64 years). Seven percent of women had stage 0 disease, 25% had stage I disease, 40% had stage II disease, and 28% had stage III disease. Fifty-four percent of women underwent mastectomy. Multilevel analyses revealed that women in the qigong group reported less depressive symptoms over time than women in the control group (P = .05). Women who had elevated depressive symptoms at the start of radiotherapy reported less fatigue (P < .01) and better overall QOL (P < .05) in the qigong group compared with the control group, and these findings were clinically significant. No significant differences were observed for sleep disturbance or cortisol slopes. CONCLUSIONS: The current results indicated that qigong may have therapeutic effects in the management of QOL among women who are receiving radiotherapy for breast cancer. Benefits were particularly evident for patients who had preintervention elevated levels of depressive symptoms.