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This paper proposes a new belief rule-based (BRB) expert system for fault diagnosis of marine diesel engines. The expert system is the first of its kind that consists of multiple concurrently activated BRB subsystems, in which each subsystem has its distinctive outputs and uses the evidential reasoning approach for inference. This novel modeling approach can be applied to identify fault modes that may co-exist. In essence, the group of BRB subsystems is used to model the nonlinear relationships between the fault features and the fault modes in marine diesel engines. The initial BRB expert system can be established by using expert experience and then optimized by using the data samples accumulated during the operation of marine diesel engines. Due to limitations in knowledge and data collected, ignorance is also considered in some BRB subsystems. The proposed BRB expert system is applied to abnormal wear detection for a kind of marine diesel engine. The performance of the BRB expert system is investigated in comparison with that of artificial neural network (ANN) models, support vector machine (SVM) models, and binary logistic regression model with fivefold cross-validation. The results show that the BRB expert system can be used for fault diagnosis of marine diesel engines in a probabilistic manner, which outperforms the ANN models, SVM models, and the binary logistic regression model in terms of accuracy and stability, and can effectively identify concurrent faults. [ABSTRACT FROM AUTHOR]

This article presents the important research findings of our study on whether delayed retirement will affect the health of Chinese workers from the perspective of sustainability of physical health. The treatment group is those who continue to work after the current statutory retirement age and the control group are those who no longer work after current statutory retirement age, and the physical health of these people is used as a dependent variable. The samples are selected from the following six regions of China: Shanghai, Chengdu, Guangzhou, Beijing, Zhengzhou, and Shenyang. Quantitative studies of physical health status of the samples are carried out. The study illustrates that for female manual workers who are younger than 63 years old, female non-manual workers who are younger than 66 years old, male manual workers who are younger than 64 years old, and male non-manual workers who are younger than 67 years old, delaying retirement, and continuing to stay in work has no effect on their physical health. After these chronological age stages, however, it has significant impact on their health. These research findings have significant impact and value for the design of China's delayed retirement policy. [ABSTRACT FROM AUTHOR]

Background: To study the effectiveness and safety of atrial fibrillation (AF) catheter ablation after pericardiectomy., Methods: Data of 24 consecutive AF patients after pericardiectomy underwent catheter ablation from five centers were collected and analyzed retrospectively. All patients were followed up at 1, 3, and 12 months after catheter ablation. Results of a repeated blood test, electrocardiogram, and echocardiography during follow-up were also collected. Adverse events such as recurrence of AF, heart failure, stroke/transient ischemic attack (TIA) and minor, and major bleeding were recorded. All patients underwent brain magnetic resonance imaging (MRI) at the end of 12 months follow-up., Results: Patients were young (20-73 years old, 48.1±11.0). Fifteen (62.5%) patients were male. CHA2DS2-VASc score (0-3, 0.21±0.41) was low in these 24 patients. Among these patients, 11 (45.8%) were paroxysmal AF, 8 (33.3%) were persistent AF, and 5 (20.8%) were long-lasting persistent AF. Left atrium diameter over 45 mm was detected in 17 (70.8%) patients. All patients underwent catheter ablation successfully. No peri-ablation procedure-related complication happened. Oral anticoagulant therapy was stopped 3 months after the final ablation. Anti-arrhythmia drugs were continued for all patients after ablation. For 12 months follow-up, AF recurred in 10 (41.7%) patients 3-7 months after the first ablation. MRI detected silent cerebral infarction (SCI) in 2 (8.3%) patients. No other adverse events occurred during follow-up., Conclusions: It is safe for AF patients to undergo catheter ablation after pericardiectomy, but the rate of recurrence of AF is high., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at http://dx.doi.org/10.21037/atm.2020.04.49). JL serves as an unpaid Section Editor of Annals of Translational Medicine from Oct 2019 to Sep 2020. The other authors have no conflicts of interest to declare., (2020 Annals of Translational Medicine. All rights reserved.)

In a previously published paper [Opt. Express26(17), 22182 (2018)], the performance of a LDPC coded OAM-based UCA FSO system exploring linear equalization with channel estimation over atmospheric turbulence has been analyzed. We find that some concepts and descriptions in [Opt. Express26(17), 22182 (2018)] are inconsistent and paradoxical. In this comment, we point out the referred inconsistency and paradox one by one and present the correct explanations.

Vortex beam carrying angular momentum (OAM) will be disturbed by the random fluctuation of the refraction index of turbulent atmosphere, resulting in intermodal crosstalk among the different OAM modes. Recent advances have demonstrated that the employment of the abruptly autofocusing vortex beams can potentially mitigate the crosstalk effect. In this paper, a new type of abruptly autofocusing vortex beams, called Airy Gaussian vortex beam array (AGVBA) is proposed. By means of multi-plane wave optics simulation, the degradation of signal mode for AGVBA propagating through isotropic atmospheric turbulence is studied. In a comparison with the conventional abruptly autofocusing vortex beams, such as the ring Airy vortex beam (RAVB) and the Airy vortex beam array (AVBA), it is shown that AGVBA achieves more centralized intensity as well as a larger spot at the focal plane, thus can effectively balance the beam spreading and beam wander effect, resulting in mitigation of intermodal crosstalk.

Androst-3β,5α,6β-triol (Triol) is a promising neuroprotective agent, but its poor solubility restricts its development into parenteral preparations. In this study, Triol is significantly solubilized by bile salt/phosphatidylcholine mixed micelles (BS/PC-MM). All BS/PC-MM systems are tested to remarkably improve the drug solubility with various stabilities after drug loading. Among them, the sodium glycocholate (SGC)/egg phosphatidylcholine (EPC) system with 2:1 ratio in weight and the total concentration of SGC and EPC of 100 mg/mL is proved to produce stable mixed micelles with high drug loading. It is found that the stability of drug-loaded mixed micelles is quite different, which might be related to the change in critical micelle concentration (CMC) after incorporating drugs. SGC/EPC and SGC/soya phosphatidylcholine (SPC) remain transparent under accelerated conditions and manifest a decreased CMC (dropping from 0.105 to 0.056 mg/mL and from 0.067 to 0.024 mg/mL, respectively). In contrast, swine bile acid-sodium salt (SBA-Na)/PC and sodium deoxycholate (SDC)/PC are accompanied by drug precipitation and reached the maximum CMC on the first and the third days, respectively. Interestingly, the variation of CMC under accelerated testing conditions highly matches the drug-precipitating event in the primary stability experiment. In brief, the bile salt/phosphatidylcholine system exists as a potential strategy of improving sterol drug solubility. CMC variation under accelerated testing conditions might be a simple and easy method to predict the stability of drug-loaded mixed micelles., Competing Interests: The authors report no conflicts of interest in this work.