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Peng YaFeng,Su XinYu,Hu LiWei,Wang Qian,Ouyang RongZhen,Sun AiMin,Guo Chen,Yao XiaoFen,Zhang Yong,Wang LiJia,Zhong YuMin 대한영상의학회 2021 Korean Journal of Radiology Vol.22 No.9
Objective: To investigate the feasibility of cine three-dimensional (3D) balanced steady-state free precession (b-SSFP) imaging combined with a non-local means (NLM) algorithm for image denoising in evaluating cardiac function in children with repaired tetralogy of Fallot (rTOF). Materials and Methods: Thirty-five patients with rTOF (mean age, 12 years; range, 7–18 years) were enrolled to undergo cardiac cine image acquisition, including two-dimensional (2D) b-SSFP, 3D b-SSFP, and 3D b-SSFP combined with NLM. End-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV), and ejection fraction (EF) of the two ventricles were measured and indexed by body surface index. Acquisition time and image quality were recorded and compared among the three imaging sequences. Results: 3D b-SSFP with denoising vs. 2D b-SSFP had high correlation coefficients for EDV, ESV, SV, and EF of the left (0.959– 0.991; p < 0.001) as well as right (0.755–0.965; p < 0.001) ventricular metrics. The image acquisition time ± standard deviation (SD) was 25.1 ± 2.4 seconds for 3D b-SSFP compared with 277.6 ± 0.7 seconds for 2D b-SSFP, indicating a significantly shorter time with the 3D than the 2D sequence (p < 0.001). Image quality score was better with 3D b-SSFP combined with denoising than with 3D b-SSFP (mean ± SD, 3.8 ± 0.6 vs. 3.5 ± 0.6; p = 0.005). Signal-to-noise ratios for blood and myocardium as well as contrast between blood and myocardium were higher for 3D b-SSFP combined with denoising than for 3D b-SSFP (p < 0.05 for all but septal myocardium). Conclusion: The 3D b-SSFP sequence can significantly reduce acquisition time compared to the 2D b-SSFP sequence for cine imaging in the evaluation of ventricular function in children with rTOF, and its quality can be further improved by combining it with an NLM denoising method.
Jun Feng Su,Ruijie Zhang,Xiaofen Hu,Amjad Ali,Zhao Wang 한국화학공학회 2022 Korean Journal of Chemical Engineering Vol.39 No.3
Calcium precipitation induced by Acinetobacter sp. H12 can simultaneously remove F− and Ca2+. Adsorption kinetics and isotherm studies showed that the defluoridation effect improved with the increase of temperature and time. The equilibrium adsorption capacity of calcium precipitation was 7.43 mg g−1 at the initial F− concentration of 10 mg L−1. Moreover, as the pH increased, the F− adsorption capacity decreased and the Ca2+ removal rate gradually increased. The adsorption process was highly fitted to the pseudo-second-order and the Freundlich isotherm. Adsorption thermodynamics analysis demonstrated that the adsorption process was a spontaneous endothermic reaction. The activation adsorption energy was 2.81 kJ mol−1 and the frequency coefficient was 10.88 h−1. EEM, SEM, XPS. XRD results indicated that the defluoridation mechanism may be due to adsorption and co-precipitation. The mechanism of Ca2+ removal may be co-precipitation with F−. It is worth-mentioning that calcium precipitation overcame the problem of adding carbon sources and avoided the microbial safety risk in the effluent. Therefore, a new insight was proposed for simultaneous remediation of Ca2+ and F− from groundwater combining the biological and chemical method.