Retrospective Electrocardiography-Gated Real-Time Cardiac Cine MRI at 3T: Comparison with Conventional Segmented Cine MRI

Chen Cui,Gang Yin,Minjie Lu,Xiuyu Chen,Sainan Cheng,Lu Li,Weipeng Yan,Yanyan Song,Sanjay Prasad,Yan Zhang,Shihua Zhao 대한영상의학회 2019 Korean Journal of Radiology Vol.20 No.1

Objective: Segmented cardiac cine magnetic resonance imaging (MRI) is the gold standard for cardiac ventricular volumetric assessment. In patients with difficulty in breath-holding or arrhythmia, this technique may generate images with inadequate quality for diagnosis. Real-time cardiac cine MRI has been developed to address this limitation. We aimed to assess the performance of retrospective electrocardiography-gated real-time cine MRI at 3T for left ventricular (LV) volume and mass measurement. Materials and Methods: Fifty-one patients were consecutively enrolled. A series of short-axis cine images covering the entire left ventricle using both segmented and real-time balanced steady-state free precession cardiac cine MRI were obtained. End-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV), ejection fraction (EF), and LV mass were measured. The agreement and correlation of the parameters were assessed. Additionally, image quality was evaluated using European CMR Registry (Euro-CMR) score and structure visibility rating. Results: In patients without difficulty in breath-holding or arrhythmia, no significant difference was found in Euro-CMR score between the two techniques (0.3 ± 0.7 vs. 0.3 ± 0.5, p > 0.05). Good agreements and correlations were found between the techniques for measuring EDV, ESV, EF, SV, and LV mass. In patients with difficulty in breath-holding or arrhythmia, segmented cine MRI had a significant higher Euro-CMR score (2.3 ± 1.2 vs. 0.4 ± 0.5, p < 0.001). Conclusion: Real-time cine MRI at 3T allowed the assessment of LV volume with high accuracy and showed a significantly better image quality compared to that of segmented cine MRI in patients with difficulty in breath-holding and arrhythmia.

Recovery of ammonium and phosphate from source-separated urine using the decomposition product of struvite pellet by microwave radiation

Shihua CHEN,Min ZHENG,Xiaomin DOU,Kangning XU 대한환경공학회 2019 대한환경공학회 학술발표논문집 Vol.2019 No.-

Left-Dominant Arrhythmogenic Cardiomyopathy: A Rare and Frequently Misdiagnosed Cardiomyopathy Associated with Heart Failure

Chen Cui,Xinyu Wang,Shihua Zhao 아시아심장혈관영상의학회 2020 Cardiovascular Imaging Asia Vol.4 No.3

A 35-year-old male with 7-year history of exertional dyspnea and abdominal distention had frequent premature ventricular contractions detected by Holter monitoring. Cardiovascular magnetic resonance (CMR) imaging demonstrated a significantly dilated left ventricle (LV) with severely reduced global systolic function. Coronary arterial stenosis was excluded with CT coronary angiography. However, transmural late gadolinium enhancement was detected by CMR in the lateral wall of the LV. The patient received cardiac transplantation. The diagnosis of left dominant arrhythmogenic right ventricular cardiomyopathy was made.

A Disturbance Observer Enhanced Composite Cascade Control with Experimental Studies

Xisong Chen,Juan Li,Jun Yang,Shihua Li 제어·로봇·시스템학회 2013 International Journal of Control, Automation, and Vol.11 No.3

The presence of strong disturbances usually causes great performance degradation of industrial process control systems. A disturbance observer (DOB) enhanced composite cascade control consisting of model predictive control (MPC), proportional-integral-derivative (PID) control, and DOB is proposed in this paper. DOB is employed here to estimate the severe disturbances and the estimated values are applied for feed-forward compensation, forming a composite control together with MPC. To evaluate the efficiency and validity of the proposed control structure, the simulation as well as experimental studies have been carried out for a level tank process which represents a typical first-order plus dead-time (FODT) industry process. Both the simulation and experimental results show that the proposed composite control method significantly improves the disturbance attenuation property of the MPC scheme in controlling such a typical industrial process.

GPIO BASED SLIDING MODE CONTROL FOR DIESEL ENGINE HIGH PRESSURE COMMON RAIL SYSTEM

Zheng Yuan,Chen Dai,Hao Sun,Shihua Li,Bifeng Yin 한국자동차공학회 2023 International journal of automotive technology Vol.24 No.1

With the rapid development of diesel engines, reducing the pressure fluctuation of the common rail has become a key factor to improve the performance of the high pressure common rail (HPCR) system. Among traditional rail pressure control approaches, the influence of time-varying disturbances on the HPCR system is not fully considered and is not well dealt with. To this end, a nonlinear model of the HPCR system is firstly established based on fluid dynamics and mechanics laws. And a composite controller based on the nonlinear model is proposed. It consists of two parts: 1) A sliding mode feedback part; 2) A disturbance feedforward compensation part based on a generalized proportional integral observer. Finally, a group of test is simulated in the AMESim simulation environment and the results are shown to demonstrate the effectiveness of the proposed method.

Does Confucianism Reduce Corporate Over-Investment? Evidence from China

Khalil Jebran,Shihua Chen,Yan Ye 한국증권학회 2019 Asia-Pacific Journal of Financial Studies Vol.48 No.2

In this study, we argue that Confucianism, as an informal institution, mitigates agency problems and thus curbs managerial over-investment behavior. Using a sample of Chinese listed firms over the period 2000 to 2015, we find strong evidence that Confucianism is negatively associated with over-investment. Furthermore, we document that the negative association between Confucianism and over-investment is weaker for state-owned enterprises than for non-state-owned enterprises. Overall, the findings enrich our understanding that informal institutions can play a significant role in influencing corporate behavior.

Expression of Yeast YAP1 in Transgenic Arabidopsis Results in Increased Salt Tolerance

Jiqiang Zhao,Shanli Guo,Shihua Chen,Hui Zhang,Yanxiu Zhao 한국식물학회 2009 Journal of Plant Biology Vol.52 No.1

Soil salinity is a major abiotic stress that lowers agricultural production around the world. Mainly caused by elevated levels of NaCl, it induces a wide range of responses in plants. In addition to ion toxicity, high salt levels can induce oxidative stress with the formation and accumulation of reactive oxygen species (ROS). We introduced the transcription factor YAP1, originally from yeast (Saccharomyces cerevisiae), into Arabidopsis thaliana (ecotype Columbia). When treated with various NaCl concentrations, transgenic plants showed increased activities of antioxidant enzymes catalase, superoxide dismutase, ascorbate peroxidase, peroxidase, glutathione S-transferase, and glutathione reductase compared with the wild-type Arabidopsis. This demonstrated that an active oxygen scavenging system was enhanced to protect plants from salt stress by equilibrating ROS metabolism. Transgenic Arabidopsis maintained higher photosynthesis levels and lower amounts of H2O2, suggesting that ROS production was reduced. Physiological analysis implied that transgenic Arabidopsis might employ multiple mechanisms to improve its salt tolerance.

Study on Crack Resistance and Calculation Model of RAC Beams Strengthened with Prestressed CFRP

Yanting Ji,Sheng Sun,Aijiu Chen,Fen Yang,Shihua Bai,Xiaoyan Han 한국콘크리트학회 2024 International Journal of Concrete Structures and M Vol.18 No.2

With the development of recycled aggregate concrete (RAC), the recovery rate of construction waste is improved, and the pollution problem is alleviated. In particular, RAC beams strengthened with prestressed carbon fiber reinforced plastics (CFRP) can exhibit improved mechanical properties, expanding RAC application. Four groups of reinforced RAC beam specimens contained 0%, 40%, 70%, and 100% recycled coarse aggregate, respectively. Each group of beams was first pre-cracked and then strengthened by prestressed CFRP with one layer and two layers respectively. Finally, the bearing capacity tests were performed for these beams. The test results show that as the recycled coarse aggregate content increases, the cracking moment and ultimate load capacity of the beam decrease, while its crack width increases. As the CFRP layer increases, the deformation and crack width of the beam decreases, while the number of cracks increases. The prestressed CFRP also exhibited tensile and peeling failure. A beam deflection calculation model was established by introducing a coefficient k representing the interaction between recycled aggregate and CFRP. The influence coefficient of concrete elongation on the crack width and average crack spacing of the beam was modified, and the crack width analysis model of the beam was established. The calculated results are in good agreement with the experimental observations. It can provide reference for the application and design of recycled concrete beams strengthened with prestressed CFRP.