1.
Combined use of a nanocarbon suspension and 99mTc-MIBI for the intra-operative localization of the parathyroid glands.
Chen, J, Zhou, Q, Feng, J, Wang, J
American journal of otolaryngology. 2018;(2):138-141
Abstract
OBJECTIVE To investigate the combined use of a nanocarbon (NC) suspension and low-dose 99mTc-MIBI for parathyroid localization during surgery in patients with secondary hyperparathyroidism (sHPT). METHODS Between March 2010 and September 2015, 40 patients with sHPT were enrolled in this study and were randomized to receive either low-dose 99mTc-MIBI+NC (group I) or low-dose 99mTc-MIBI (group II). Pre- and post-operative serum levels of intact PTH (iPTH), calcium and phosphorus between groups were compared and the intra-operative radioactive counts of the parathyroid glands were measured. RESULTS The post-operative iPTH level was significantly lower in patients of group I (24.2±31ng/L) than in those of group II (106±155ng/L) (P=0.03) while there were no significant differences in intra-operative parathyroid gland radioactive counts between the groups. The duration of the surgical procedure was shorter for patients of group I than patients of group II. There were no serious intra-operative or post-operative complications. CONCLUSION The combined use of an NC suspension and 99mTc-MIBI for patients with sHPT is strongly recommended for the localization of parathyroid glands during surgery and is likely to improve clinical outcomes for patients.
2.
Greenhouse wastewater treatment by baffled subsurface-flow constructed wetlands supplemented with flower straws as carbon source in different modes.
Chang, J, Ma, L, Chen, J, Lu, Y, Wang, X
Environmental science and pollution research international. 2017;(2):1578-1587
Abstract
Four laboratory-scale baffled subsurface-flow constructed wetlands (BSCWs) were established for the treatment of greenhouse wastewater containing high levels of nitrate and sulfate in the present study. Each BSCW microcosm involved a treatment zone and another post-treatment zone with a surface area ratio of 2:1. Evenly mixed straws of carnation and rose (w/w: 1/1), two common ornamental flowers, were supplemented as an organic carbon source into the treatment zone through a hydrolysis zone (CW 1), decentralized vertically installed perforated pipes (CW 2), and centralized pipes (CW 3 in the figures), except the blank system. Removals and transformations of nitrogen and sulfate as well as carbon release in the BSCWs were investigated and comparatively assessed. Results showed that the supplements of flower straws could greatly enhance both the nitrate and sulfate removals, and good performance was achieved during the beginning operation period of 30 days, followed by decline due to insufficient organic carbon supply. Nitrate removal efficiency was significantly higher and more stable compared to sulfate. The highest removal rates of nitrate and sulfate were achieved in the CW 3, with a mean value of 4.33 g NO3--N·m-2 d-1 and 2.74 g SO42--S·m-2 d-1, respectively, although the differences among the experimental microcosms were not statistically significant. However, almost the same TN removal rate (3.40-3.47 g N·m-2 d-1) was obtained due to the productions of NO2--N and NH4+-N and leaching of organic N from the straws. High contents of organic carbon and colored substance were leached from the straws during the initial 10 days, but dropped rapidly to low levels, and could hardly determined after 30 days operation. The post-treatment zone could further eliminate various contaminants, but the capability was limited. Inorganic carbon (IC) concentration was detected to be a highly good indicator for the estimation of nitrate and sulfate removal efficiencies of the BSCWs, particularly for nitrate.
3.
Effect of carbon source and COD/NO₃⁻-N ratio on anaerobic simultaneous denitrification and methanogenesis for high-strength wastewater treatment.
Xie, L, Chen, J, Wang, R, Zhou, Q
Journal of bioscience and bioengineering. 2012;(6):759-64
Abstract
The effect of carbon source and COD/NO(3)(-)-N ratio on denitrification and methanogenesis in mixed methanogenic matrix was investigated in this study. Industrial wastewater, anaerobic treated cassava stillage (CS) and glucose synthetic wastewater were used as carbon sources respectively for comparison. Experimental results showed that denitrification was the main nitrate reduction pathway for all COD/NO(3)(-)-N ratios tested in two substrates. Simultaneous denitrification and methanogenesis occurred at COD/NO(3)(-)-N higher than 7 regardless of carbon sources. Incomplete denitrification was observed at COD/NO(3)(-)-N ratio below 7 in both the anaerobic effluent of CS and glucose-fed cultures due to the insufficient available organic carbon. The nature of carbon sources was observed to play a key role in the nitrate and organic carbon utilization rates. COD/NO(3)(-)-N ratio had a strong effect on the organic matter utilization pathways. Methanization consumed more organic matter than denitrification with further increase of COD/NO(3)(-)-N ratio above 7 in two substrates. Results of VFA variation suggested that propionate and butyrate were preferably utilized by the denitrifiers than acetate.
4.
Altered ecosystem carbon and nitrogen cycles by plant invasion: a meta-analysis.
Liao, C, Peng, R, Luo, Y, Zhou, X, Wu, X, Fang, C, Chen, J, Li, B
The New phytologist. 2008;(3):706-714
Abstract
Plant invasion potentially alters ecosystem carbon (C) and nitrogen (N) cycles. However, the overall direction and magnitude of such alterations are poorly quantified. Here, 94 experimental studies were synthesized, using a meta-analysis approach, to quantify the changes of 20 variables associated with C and N cycles, including their pools, fluxes, and other related parameters in response to plant invasion. Pool variables showed significant changes in invaded ecosystems relative to native ecosystems, ranging from a 5% increase in root carbon stock to a 133% increase in shoot C stock. Flux variables, such as above-ground net primary production and litter decomposition, increased by 50-120% in invaded ecosystems, compared with native ones. Plant N concentration, soil NH+4 and NO-3 concentrations were 40, 30 and 17% higher in invaded than in native ecosystems, respectively. Increases in plant production and soil N availability indicate that there was positive feedback between plant invasion and C and N cycles in invaded ecosystems. Invasions by woody and N-fixing plants tended to have greater impacts on C and N cycles than those by herbaceous and nonN-fixing plants, respectively. The responses to plant invasion are not different among forests, grasslands, and wetlands. All of these changes suggest that plant invasion profoundly influences ecosystem processes.