There is growing in interest in deploying nanoscale zero valent iron (NZVI) in permeable reactive barriers (PRBs) for groundwater remediation. In the present study a series of packed-column experiments were conducted in order to investigate the effectiveness of phosphorus removal from groundwater using NZVI and bimetallic NZVI/Cu as a reactive material within permeable reactive barriers (PRBs), also to help to inform on the design of the PRB. Experiments were conducted using a lab-scale column of 65 cm length and 10 cm inner diameter using two types of silica sand, river sand and standard sand, as a filling porous material. Seven sets of column experiments were established in order to investigate the effect of: different delivery methods of the reactive material into porous media (layers-packing or injection); modifying NZVI composition by copper addition; supporting materials and the flowrate change. The physical characteristics of the reactive and supporting materials were investigated using X-ray diffraction (XRD) analysis, transmission electron microscopy (TEM), scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDS).These analyses revealed that doping of NZVI surface with copper enhanced performance in terms of phosphorus removal 2.2 times more than pure NZVI. Moreover, the lower flowrate (10 ml/min) demonstrated improved phosphorus removal by 22 % compared with higher flowrate (60 ml/min). Additionally, the contact time between NZVI and phosphorus had a crucial effect on the long-term phosphorus removal efficiency and should to be considered in the preliminary design of PRBs. Overall, geochemical properties as well as the characteristics of the supporting materials were considered to be key parameters in the removal process of phosphorus by bimetallic NZVI/Cu. Further studies should be performed based on a statistical analysis model in order to integrate such presented results in the determination of the optimum design and conditions of PRBs towards better performance in the real in-situ remediation applications.
Objective: We previously found that mirabegron exerts a relaxant effect in the presence of the β 3 -adrenoceptor antagonist SR58894A during carbachol-induced contraction in human and pig detrusor. The aim of this study was to explore the possible mechanism underlying the relaxant effects of mirabegron using detrusor smooth muscle. Methods: Human tissue was obtained from urinary bladders of patients undergoing radical cystectomy at Kyushu University and Harasanshin Hospital. Pig tissue was obtained from an abattoir. Tension force (organ bath experiments) was measured in intact or permeabilised (α-toxin or β-escin) detrusor smooth muscle strips. The contribution of cAMP-dependent signaling and the inhibition of Ca 2+ sensitization to the relaxant effects of mirabegron were characterized using 1 μM SR58894A, 100 μM SQ22536 (an adenylyl cyclase inhibitor), 10 μM H-89 (a protein kinase [PK] A inhibitor), 10 μM Y-27632 (a selective Rho kinase inhibitor), and 10 μM GF-109203X (a selective PKC inhibitor). Results: 30 μM Mirabegron impaired carbachol (0.03-1 μM)-induced contraction in human detrusor smooth muscle. SR58894A only partially attenuated the relaxant effects of mirabegron in human and pig detrusor strips precontracted with 1 μM carbachol. In α-toxin-permeabilized detrusor strips, tension force at 1 μM [Ca 2+ ] i was decreased by mirabegron in a concentrationdependent manner. The relaxant effect of mirabegron was only slightly attenuated by H-89 and not significantly affected by SQ22536. Y-27632 potentiated the relaxation response to mirabegron, but attenuated responses to cAMP; GF-109203X had little effect. Mirabegron but not cAMP had a notable relaxant effect in the pig detrusor smooth muscle permeabilized with β-escin. Conclusions: Mirabegron-induced relaxation of pig and human detrusor smooth muscle occurs via both a β 3 -adrenoceptor/cAMP-dependent and -independent pathway. K E Y W O R D S β 3 -Adrenoceptors, mirabegron, smooth muscle, urinary bladder
Objective To develop a new mouse model of underactive bladder (UAB) caused by chronic bladder outlet obstruction (BOO). Methods BOO was created in 6‐week‐old male C57BL/6 mice using surgery to loosely place a silver jump ring around the bladder neck of each mouse. Micturition behavior (assessed with a metabolic cage) and cystometry were used to evaluate bladder function at 8 and 16 weeks after BOO. Following completion of the functional studies, the bladders of the mice were excised, weighed, and subjected to histological analysis. Results Micturition behavior analysis showed that mice subjected to BOO for 16 weeks had a lower frequency of micturition (7.3 ± 1.1 vs 12.5 ± 3.0 times/d, P < .05) and volume per void (106.0 ± 0.1 vs 133.9 ± 3.2 μL, P < .05) than mice subjected to BOO for 8 weeks. Cystometry revealed that mice subjected to BOO for 16 weeks had lower baseline pressure (8.4 ± 0.6 vs 14.0 ± 0.7 cmH2O, P < .01) and micturition pressure (13.9 ± 1.1 vs 42.8 ± 1.7 cmH2O, P < .05) than mice subjected to BOO for 8 weeks. BOO caused progressive increases in bladder mass and collagen deposition over time. Conclusions We successfully established a novel mouse model of UAB using surgery to place a silver jump ring loosely on the bladder neck. BOO initially induced bladder overactivity but subsequently resulted in UAB due to deterioration of detrusor smooth muscle contractility and progressive deposition of collagen in the bladder wall.
Background and Objective: In addition to the reduction of risk of COVID-19 transmission and mortality, vaccination and compliance with the preventive measures of COVID-19 may have important additional benefits for the improvement of mental health. This study examined the levels and determinants of vaccination, compliance with preventive measures, and anxiety, depression and stress among Bangladeshi adults. It also examined the effects of vaccination and compliance with preventive measures on mental health status among Bangladeshi adults. Methods: Data for the study come from an online survey conducted during November and December 2021 among Bangladeshi adults. A total of 615 adults participated in the survey. A 21-item Depression, Anxiety, and Stress scale (DASS 21) were used for collecting data on mental health. Both descriptive and inferential statistical methods including multiple logistic regression were used for data analysis. Results: About 69% of Bangladeshi adults were vaccinated with at least one dose; 87% of adults believed that vaccines are moderate to highly effective in reducing COVID-19 infection. Among the preventive measures during a pandemic, the level of complete compliance with wearing masks and hand washing was almost universal, while the compliance level with other preventive measures was moderate. Vaccinated people had a 55% (OR=0.45; 95%CI:0.26-0.82), 67% (OR=0.33; 95%CI:0.12-0.91), and 44% (OR=0.56; 95%CI:0.27-0.97) lower chance of suffering from depression, anxiety, and stress, respectively than non-vaccinated people. People with complete compliance had 64% (OR= 0.36; 95%CI:0.18-0.72), 71% (OR=0.29; 95%CI:0.15-0.58), and 74% (OR=0.26; 95%CI:0.13-0.50) lower risk of suffering from depression, anxiety, and stress, respectively, than respondents with irregular preventive behaviors. Conclusion: This study documents the important psychological benefits of vaccination and compliance with preventive measures of COVID-19.
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