Effect of Mixture Flow Rate on Emission Characteristics of Laminar Premixed CH4/Air Flame with Changing Combustor Pressure

Hai-quan Ma,Jae-hyeok Song,Ki-joong Kang,Gyung-min Choi,Duck-jool Kim 한국연소학회 2012 KOSCOSYMPOSIUM논문집 Vol.- No.44

Utility of Readout-Segmented Echo-Planar Imaging-Based Diffusion Kurtosis Imaging for Differentiating Malignant from Benign Masses in Head and Neck Region

Gao Ma,Xiao-Quan Xu,Hao Hu,Guo-Yi Su,Jie Shen,Hai-Bin Shi,Fei-Yun Wu 대한영상의학회 2018 Korean Journal of Radiology Vol.19 No.3

Objective: To compare the diagnostic performance of readout-segmented echo-planar imaging (RS-EPI)-based diffusion kurtosis imaging (DKI) and that of diffusion-weighted imaging (DWI) for differentiating malignant from benign masses in head and neck region. Materials and Methods: Between December 2014 and April 2016, we retrospectively enrolled 72 consecutive patients with head and neck masses who had undergone RS-EPI-based DKI scan (b value of 0, 500, 1000, and 1500 s/mm2) for pretreatment evaluation. Imaging data were post-processed by using monoexponential and diffusion kurtosis (DK) model for quantitation of apparent diffusion coefficient (ADC), apparent diffusion for Gaussian distribution (Dapp), and apparent kurtosis coefficient (Kapp). Unpaired t test and Mann-Whitney U test were used to compare differences of quantitative parameters between malignant and benign groups. Receiver operating characteristic curve analyses were performed to determine and compare the diagnostic ability of quantitative parameters in predicting malignancy. Results: Malignant group demonstrated significantly lower ADC (0.754 ± 0.167 vs. 1.222 ± 0.420, p < 0.001) and Dapp (1.029 ± 0.226 vs. 1.640 ± 0.445, p < 0.001) while higher Kapp (1.344 ± 0.309 vs. 0.715 ± 0.249, p < 0.001) than benign group. Using a combination of Dapp and Kapp as diagnostic index, significantly better differentiating performance was achieved than using ADC alone (area under curve: 0.956 vs. 0.876, p = 0.042). Conclusion: Compared to DWI, DKI could provide additional data related to tumor heterogeneity with significantly better differentiating performance. Its derived quantitative metrics could serve as a promising imaging biomarker for differentiating malignant from benign masses in head and neck region.

Induction Chemotherapy Plus Concurrent Chemoradiotherapy versus Concurrent Chemoradiotherapy Alone in Locoregionally Advanced Nasopharyngeal Carcinoma in Children and Adolescents: A Matched Cohort Analysis

Yang Li,Lin-Quan Tang,Li-Ting Liu,Shan-Shan Guo,Yu-Jing Liang,Xue-Song Sun,Qing-Nan Tang,Jin-Xin Bei,Jing Tan,Shuai Chen,Jun Ma,Chong Zhao,Qiu-Yan Chen,Hai-Qiang Mai 대한암학회 2018 Cancer Research and Treatment Vol.50 No.4

Purpose The purpose of this study was to evaluate the long-term clinical outcome and toxicity of induction chemotherapy (IC) followed by concomitant chemoradiotherapy (CCRT) compared with CCRT alone for the treatment of children and adolescent locoregionally advanced nasopharyngeal carcinoma (LACANPC). Materials and Methods A total of 194 locoregionally advanced nasopharyngeal carcinoma patients younger than 21 years who received CCRT with or without IC before were included in the study population. Overall survival (OS) rate, progression-free survival (PFS) rate, locoregional recurrence-free survival (LRFS) rate, and distant metastasis-free survival (DMFS) rate were assessed by the Kaplan-Meier method and a log-rank test. Treatment toxicities were clarified and compared between two groups. Results One hundred and thiry of 194 patients received IC+CCRT. Patients who were younger and with more advanced TNM stage were more likely to receive IC+CCRT and intensive modulated radiotherapy. The addition of IC before CCRT failed to improve survival significantly. The matched analysis identified 43 well-balanced patients in both two groups. With a median follow-up of 51.5 months, no differences were found between the IC+CCRT group and the CCRT group in 5-year OS (83.7% vs. 74.6%, p=0.153), PFS (79.2% vs. 73.4%, p=0.355), LRFS (97.7% vs. 88.2%, p=0.083), and DMFS (81.6% vs. 81.6%, p=0.860). N3 was an independent prognostic factor predicting poorer OS, PFS, and DMFS. The addition of IC was associated with increased rates of grade 3 to 4 neutropenia. Conclusion This study failed to demonstrate that adding IC before CCRT could provide a significant additional survival benefit for LACANPC patients. Further investigations are warranted.

Experimental Study on Magnesium Sulfate Cement Concrete Splices of Widened Box Girder

Li-fang Zhang,Jun Yan,Hai-yan Ma,Hong-fa Yu,Ying Wang,Qi-quan Mei 대한토목학회 2021 KSCE JOURNAL OF CIVIL ENGINEERING Vol.25 No.12

The connecting part of bridge widening undertakes complicated forces and tends to crack. Basic magnesium sulfate cement concrete has excellent properties such as ideal early strength and tensile strength, meeting the performance requirements of joint materials. Experiments of two spliced box girder specimens with C40 basic magnesium sulfate cement concrete (MC) and normal Portland cement concrete (NC) as joint materials are carried out. Concrete strain, reinforcement strain, deflection and crack propagation law of the joint section are tested and analyzed under symmetrical loading at the cantilever of the box girders. The study shows when MC material is used in the splicing section, the joint section showed a multi-cracks failure mode with an ultimate load ratio of 0.99 and a maximum crack width of 1.3 mm; NC joint section has only three longitudinal cracks with an ultimate load ratio of 0.97 and a maximum crack width of 0.98 mm. Under the same load, the crack width and the deflection of mid-span MC joint section are greater than which of NC joint section. The maximum deflection of NC splicing section is 1.20 mm, which is 1/633 of the calculating span length. The maximum deflection of MC spliced section is 2.03 mm, which is 1/374 of the calculating span length. Comparison of the maximum deflection and the maximum crack width shows that MC material has better ductility.

Radiological gastrostomy: A comparative analysis of different image-guided methods

Hong-Tao Hu,Hang Yuan,Chen-Yang Guo,Quan-Jun Yao,Xiang Geng,Hong-Tao Cheng,Jun-Li Ma,Yan Zhao,Li Jiang,Yu-Qing Zhao,Hai-Liang Li 소화기인터벤션의학회 2021 Gastrointestinal Intervention Vol.10 No.2

Background: Radiographic guided percutaneous gastrostomy has become a safe and effective enteral nutrition method for patients who can not eat by mouth. Fluoroscopy, computed tomography (CT) and cone-beam CT have been routinely used clinically. The aim of this study was to compare the advantages and disadvantages of percutaneous gastrostomy using different radiographic guided methods. Methods: We retrospectively analyzed the clinical data of 538 patients undergoing percutaneous gastrostomy in our department. According to the image guidance method used in gastrostomy, the patients were divided into groups A by fluoroscopy guidance, group B by fluoroscopy combined with C-arm CT guidance, and group C with the whole process CT guidance. The gastrostomy success rate, complication rate, procedure time, and patient radiation dose were analyzed in the three groups. Results: Among 538 patients, 534 were successful and the success rates are 94.3%, 99.3%, and 100% in group A, B, and C, respectively (P > 0.05). There were 3 cases occurred postoperative bleeding as serious adverse events and transferred to surgical gastrostomy. The minor complications include local infection, hyperplasia of granulation tissue, tube obstruction or prolapse, and local pain of the ostomy. The minor complication rates were 10.5%, 10.4%, and 7.7% in group A, B, and C, respectively (P > 0.05). The average procedure time was 25.57 ± 5.99 minutes, 29.01 ± 6.63 minutes, and 45.47 ± 8.98 minutes, respectively (χ2 = 87.98, P < 0.001). The average radiation dosage was 27.30 ± 19.27 mGy, 145.07 ± 106.08 mGy, and 2,590.26 ± 1,088.22 mGy, respectively (χ2 = 204.44, P < 0.001). Conclusion: There were no significant differences in the success rates and complication rates of gastrostomy under the three guiding methods. For difficult cases, CT-guided gastrostomy may be a very useful supplemental method.

Effects of Oxygen Content on the Simultaneous Microbial Removal of SO2 and NOx in Biotrickling Towers

Xing Chun Wang,Xiao Yi Bi,Pei Shi Sun,Jin Quan Chen,Ping Zou,Xiao Ming Ma,Jing Zhang,Hai Yu Wang,Xiao Yi Xu 한국생물공학회 2015 Biotechnology and Bioprocess Engineering Vol.20 No.5

This study uses microbial methods to research the influence of oxygen (O2) content on the removal efficiency of sulfur dioxide (SO2) and nitrogen oxides (NOx) in a tandem twin-towers desulfurization and denitrification process system. Oxygen can play a significant role in biotrickling towers. Other important factors had already been optimized prior to the study, including inlet concentration, gas flow rate, and temperature. SO2 and NOx were prepared by a chemical method. A gas flow meter was used to regulate nitrogen (N2) that had been stored in steel cylinders. In this way, the O2 content was adjusted in the biotrickling towers by controlling the N2 flow rate. Five gradients of O2 content were selected for investigation, namely 4, 8, 12, 16, and 20%. Results indicated that the SO2 removal efficiency from mixed gas (SO2 and NOx) can reach 100%, from all of the five O2 gradients, in biotrickling towers. In a tandem twin-towers desulfurization and denitrification process system, the NOx removal efficiency and the inlet concentration of nitrogen dioxide (NO2) gradually increased as the O2 content increased. Specifically, the average removal efficiency of NOx increased from 49.28 to 80.85% as the O2 content changed from 4 to 20%. The oxygen levels influenced the removal of NOx but the SO2 removal efficiency in mixed gas was always stable.

Radiological gastrostomy: A comparative analysis of different image-guided methods

Hong-Tao Hu,Hang Yuan,Chen-Yang Guo,Quan-Jun Yao,Xiang Geng,Hong-Tao Cheng,Jun-Li Ma,Yan Zhao,Li Jiang,Yu-Qing Zhao,Hai-Liang Li 소화기인터벤션의학회 2021 International journal of gastrointestinal interven Vol.10 No.2

Background: Radiographic guided percutaneous gastrostomy has become a safe and effective enteral nutrition method for patients who can not eat by mouth. Fluoroscopy, computed tomography (CT) and cone-beam CT have been routinely used clinically. The aim of this study was to compare the advantages and disadvantages of percutaneous gastrostomy using different radiographic guided methods. Methods: We retrospectively analyzed the clinical data of 538 patients undergoing percutaneous gastrostomy in our department. According to the image guidance method used in gastrostomy, the patients were divided into groups A by fluoroscopy guidance, group B by fluoroscopy combined with C-arm CT guidance, and group C with the whole process CT guidance. The gastrostomy success rate, complication rate, procedure time, and patient radiation dose were analyzed in the three groups. Results: Among 538 patients, 534 were successful and the success rates are 94.3%, 99.3%, and 100% in group A, B, and C, respectively (P > 0.05). There were 3 cases occurred postoperative bleeding as serious adverse events and transferred to surgical gastrostomy. The minor complications include local infection, hyperplasia of granulation tissue, tube obstruction or prolapse, and local pain of the ostomy. The minor complication rates were 10.5%, 10.4%, and 7.7% in group A, B, and C, respectively (P > 0.05). The average procedure time was 25.57 ± 5.99 minutes, 29.01 ± 6.63 minutes, and 45.47 ± 8.98 minutes, respectively (χ2 = 87.98, P < 0.001). The average radiation dosage was 27.30 ± 19.27 mGy, 145.07 ± 106.08 mGy, and 2,590.26 ± 1,088.22 mGy, respectively (χ2 = 204.44, P < 0.001). Conclusion: There were no significant differences in the success rates and complication rates of gastrostomy under the three guiding methods. For difficult cases, CT-guided gastrostomy may be a very useful supplemental method.

Aberrant microRNAs Expression in CD133+/CD326+ Human Lung Adenocarcinoma Initiating Cells from A549

Sheng Lin,Zheng-tang Chen,Jian-guo Sun,Jing-bo Wu,Hai-xia Long,Cong-hui Zhu,Tong Xiang,Hu Ma,Zhong-quan Zhao,Quan Yao,An-mei Zhang,Bo Zhu 한국분자세포생물학회 2012 Molecules and cells Vol.33 No.3

Increasing evidence demonstrates that miRNAs are in-volved in the dysregulation of tumor initiating cells (TICs) in various tumors. Due to a lack of definitive markers, cell sorting is not an ideal separation method for lung adeno-carcinoma initiating cells. In this study, we combined pa-clitaxel with serum-free medium cultivation (inverse-induc-tion) to enrich TICs from A549 cells, marked by CD133/ CD326, defined features of stemness. We next investigated aberrant microRNAs in this subpopulation compared to normal cells with miRNA microarray and found that 50 miRNAs exhibited a greater than 2-fold change in expres-sion. As further validation, 10 miRNAs were chosen to perform quantitative RT-PCR on the A549 cell line and primary samples. The results suggest that aberrant ex-pression of miRNAs such as miR-29ab, miR-183, miR-17-5p and miR-127-3P may play an important role in regulat-ing the bio-behavior of TICs.

Patterns of Failure and Survival Trends in 3,808 Patients with Stage II Nasopharyngeal Carcinoma Diagnosed from 1990 to 2012: A Large-Scale Retrospective Cohort Study

Xue-Song Sun,Di-Han Liu,Sai-Lan Liu,Qiu-Yan Chen,Shan-Shan Guo,Yue-Feng Wen,Li-Ting Liu,Hao-Jun Xie,Qing-Nan Tang,Yu-Jing Liang,Xiao-Yun Li,Jin-Jie Yan,Ming-Huang Hong,Jun Ma,Lin-Quan Tang,Hai-Qiang M 대한암학회 2019 Cancer Research and Treatment Vol.51 No.4

Purpose The purpose of this study was to investigate the survival trends and patterns of failure in patients with stage II nasopharyngeal carcinoma (NPC) treated with radiotherapy (RT) and chemotherapy over the last 20 years. Materials and Methods Thirty-eight hundred and eight patients diagnosed with stage II NPC between January 1990 and December 2012 were involved in this retrospective cohort study. All patients were treated with RT. According to the main imaging techniques and RT technology, we categorized these patients into four calendar periods: 1990-1996, 1997-2002, 2003-2007, and 2008-2012. Overall survival (OS), progression-free survival (PFS), locoregional relapse-free survival (LRFS), and distant metastasis–free survival (DMFS) were served as the clinical outcome. Results After a median follow-up period of 84.7 months, we observed increasing trends in survival and disease control. The 3- and 5-year OS rates increased from 87.1% and 78.7% in the first calendar period to 97.4% and 94.5% in the last calendar period, respectively (p < 0.001). Additionally, significant increasing trends could be seen in the PFS and LRFS during the four calendar periods. In the subgroup analysis, the LRFS in patients older than 50 years at diagnosis showed greater improvement than younger patients. However, the rate of distant metastasis was stable and relatively low, as the 5-year DMFS ranged from 90.5% to 94.7% among the four calendar periods. Conclusion The survival rates in patients with stage II NPC showed increasing trends from 1990 to 2012. The advance of RT provided excellent locoregional control and enhanced OS.