Treatment performance and microbial response to dibutyl phthalate contaminated wastewater in vertical flow constructed wetland mesocosms
CHEMOSPHERE
Authors: Li, Tiancui; Fan, Yaocheng; Cun, Deshou; Song, Xiaoyong; Dai, Yanran; Wang, Feihua; Wu, Chenxi; Liang, Wei
Abstract
Phthalic acid esters (PAEs), especially dibutyl phthalate (DBP) pollution in the environment, have attracted worldwide attention. Four Phragmites australis-based, mesocosm-scale vertical flow constructed wetlands (VFCWs) with different hydraulic loading rates (HLRs) were operated for one year to study the removal efficiency and mechanisms of DBP in the reclaimed water. The average removal efficiencies for DBP were 93.77 +/- 3.27%, 94.9 +/- 2.60% and 97.0 +/- 3.00% in the VFCWs under HLRs of 0.33, 0.22 and 0.11 m/d, respectively. DBP can be accumulated and degraded by wetland plants and its concentration in the roots (0.256-8.45 mg/kg) were higher than in the leaves (0.243-0.482 mg/kg). The concentrations of primary and secondary metabolites mono-n-butyl phthalate (MBP) and phthalic acid (PA) were 0.142 -2.35 mg/kg and 0.113-0.545 mg/kg respectively in the plant tissues. The concentrations of DBP were 38.2-271 mu g/kg in the substrates. Mass balance for DBP indicates that the estimated plant uptake and substrate adsorption of total DBP is negligible. This suggests that biodegradation and other process are the primary pathways for DBP removal in VFCWs. The results of 16S rDNA and ITS rDNA high-throughput sequencing indicated that both bacterial and fungal community diversity decreased with the exposure of DBP. Janthinobacterium, Flavobacterium and Curvularia genera may be the main participants in the biodegradation of DBP in the CWs. (C) 2019 Elsevier Ltd. All rights reserved.
Effect of ultrasound-guided L1/L2 paravertebral block in decreasing drug requirements during general anesthesia in patients undergoing hip surgeries; randomized controlled trial
EGYPTIAN JOURNAL OF ANAESTHESIA
Authors: Abdelhamid, Bassant Mohamed; Belita, Mohamed Ibrahim; Gomaa, Hala Mostafa; Ali, Mohamed Saeid; Mohamed, Ahmed Abdalla; Hassan, Mohamed Mahmoud
Abstract
Background: The aim of this study is to investigate that combinig Lumbar paravertebral block and GA decreases postoperative pain, blood loss and the need for hypotensive drugs. Methods: After ethical committee approval. A randomized, controlled; double-blinded study registered (NCTR 03422354). The study was conducted in Cairo university hospital from 15/02/2018/to 21/06/2018. Seventy-four patients were randomly allocated into two groups using computerized generated random tables: Group P: 37 patients received single-shot L1-L2 paravertebral block before GA. And Group G: 37 patients received GA. The primary outcome was the required dose of hypotensive drugs in both groups. Results: There were no statistical differences in hypotensive drug requirements between both groups. On the other hand, there were remarkable differences in all analgesics that were used in both groups as the total doses were much less in the group (P) than in the group (G). There was a statistically significant decrease in both MBP and HR in the group (P) in 30, 60 and 120 min after induction of anesthesia. Group P showed a lower level of VAS with statistical differences in the first 30 min after recovery and the subsequent 4 h (2 and 4). After 4 h the VAS was low in both groups and was noncomparable between the two groups. Conclusion: U/S guided L1/L2 PVB produces proper intraoperative hemodynamic control. It is also a safe and excellent alternative of analgesia that decreases the perioperative opioids requirements. However, there were no difference in the total dose of hypotensive drugs and the total blood loss.