The fault tree analysis (FTA) is a well-structured, precise, and powerful tool that can be used to assist the analyst in identification, evaluation, and analysis of all basic causes and paths ending up to the occurrence of a certain event. In the conventional approach, the probability of the basic events is considered either as a precise point value or as a random timedependent variable. However, due to the inherent imprecision and uncertainty of the available data, it is often impossible to obtain an exact estimation of an event occurrence rate or its distribution function. In such cases, the fuzzy approach is among the best choices for analysing the system. This article presents a comprehensive and transparent study on the evaluation of the railway safety risks using the fuzzy FTA. For this purpose, a method for quantification and evaluation of the fault tree in the fuzzy environment is proposed. The method that is presented in this article is based on modifying the weighted averaging according to the levels defuzzification method. Therefore, it proposes a new importance distribution function for the level sets during the defuzzification process. Furthermore, it extends the minimal cut-set and the Fussell-Vesely importance measures of the conventional approach into the fuzzy environment. These importance measures can be effectively used for the ranking of the minimal cut-sets and the basic events according to their contribution to the top event probability. Also, a practical case study regarding a passenger train derailment is used to describe the proposed concepts. The planned methodology is relevant in several engineering applications.

ImportanceThe optimal treatment of intermediate-high–risk pulmonary embolism (PE) remains unknown.ObjectiveTo assess the effect of conventional catheter-directed thrombolysis (cCDT) plus anticoagulation vs anticoagulation monotherapy in improving echocardiographic measures of right ventricle (RV) to left ventricle (LV) ratio in acute intermediate-high–risk PE.Design, Setting, and ParticipantsThe Catheter-Directed Thrombolysis vs Anticoagulation in Patients with Acute Intermediate-High–Risk Pulmonary Embolism (CANARY) trial was an open-label, randomized clinical trial of patients with intermediate-high–risk PE, conducted in 2 large cardiovascular centers in Tehran, Iran, between December 22, 2018, through February 2, 2020.InterventionsPatients were randomly assigned to cCDT (alteplase, 0.5 mg/catheter/h for 24 hours) plus heparin vs anticoagulation monotherapy.Main Outcomes and MeasuresThe proportion of patients with a 3-month echocardiographic RV/LV ratio greater than 0.9, assessed by a core laboratory, was the primary outcome. The proportion of patients with an RV/LV ratio greater than 0.9 at 72 hours after randomization and the 3-month all-cause mortality were among secondary outcomes. Major bleeding (Bleeding Academic Research Consortium type 3 or 5) was the main safety outcome. A clinical events committee, masked to the treatment assignment, adjudicated clinical outcomes.ResultsThe study was prematurely stopped due to the COVID-19 pandemic after recruiting 94 patients (mean [SD] age, 58.4 [2.5] years; 27 women [29%]), of whom 85 patients completed the 3-month echocardiographic follow-up. Overall, 2 of 46 patients (4.3%) in the cCDT group and 5 of 39 patients (12.8%) in the anticoagulation monotherapy group met the primary outcome (odds ratio [OR], 0.31; 95% CI, 0.06-1.69; P = .24). The median (IQR) 3-month RV/LV ratio was significantly lower with cCDT (0.7 [0.6-0.7]) than with anticoagulation (0.8 [0.7-0.9); P = .01). An RV/LV ratio greater than 0.9 at 72 hours after randomization was observed in fewer patients treated with cCDT (13 of 48 [27.0%]) than anticoagulation (24 of 46 [52.1%]; OR, 0.34; 95% CI, 0.14-0.80; P = .01). Fewer patients assigned to cCDT experienced a 3-month composite of death or RV/LV greater than 0.9 (2 of 48 [4.3%] vs 8 of 46 [17.3%]; OR, 0.20; 95% CI, 0.04-1.03; P = .048). One case of nonfatal major gastrointestinal bleeding occurred in the cCDT group.Conclusions and RelevanceThis prematurely terminated randomized clinical trial of patients with intermediate-high–risk PE was hypothesis-generating for improvement in some efficacy outcomes and acceptable rate of major bleeding for cCDT compared with anticoagulation monotherapy and provided support for a definitive clinical outcomes trial.Trial RegistrationClinicalTrials.gov Identifier: NCT05172115

In this manuscript, a novel nanocomposite PMo11CdO39@MnFe2O4 (PMo11Cd@MnFe2O4) based on ceramic (MnFe2O4) and mono substitute polyoxometalate (PMo11Cd) was synthesized successfully via sol–gel method in extremely mild conditions. PMo11Cd@MnFe2O4 has been proposed as a new heterogeneous inorganic nanocatalyst for highly efficient deep desulfurization of model fuel/real gasoline. The successful synthesis of as‐prepared compounds was proved by FT‐IR, XRD, SEM, and EDX techniques. The catalytic oxidative desulfurization (CODS) was performed under mild conditions in the presence of 50 ml of model fuel/real gasoline, 3 ml of oxidant with 2:1 H2O2/CH3COOH volume ratio. The efficiency was further detailed by pursuing different effective properties on the CODS process like dosage effects, different oxidation system and different catalyst effects. The best results of PMo11Cd@MnFe2O4 nanocatalyst attained via 0.1 g of dosage and H2O2/CH3COOH as oxidation system. The process obeyed the pseudo‐first‐order kinetics as the correlation factor was close to unity. In the end, the PMo11Cd@MnFe2O4 demonstrated good reusability after 5 runs.

In the view of practical applications, synthesizing green and recyclable nanocatalysts under mild conditions were always been desired by scientists and industries. In this study, in order to obtain the clean gasoline, a novel nanocomposite (PMo12O40@MnFe2O40) based on polyoxometalate and ceramic was synthesized successfully with Aloe vera leaf extract by sol–gel method in extremely mild conditions. PMo12O40@MnFe2O40 is proposed as a green new recyclable and economic nanocatalyst for deep catalytic oxidative desulfurization (CODS) of real and model fuel (DBT, Th, and BT). The characterizations were carried out by different analysis methods including Fourier transform infrared (FT‐IR), X‐ray diffraction (XRD), scanning electron microscopy (SEM), and energy‐dispersive X‐ray spectroscopy (EDX), and the successful synthesis and immobilization were approved. After conducting the PMo12O40@MnFe2O4 in the CODS processes, optimum effective properties were investigated. The average efficiency of the nanocatalyst was found 98% for DBT and 96% for real fuel by optimum values of the properties (catalyst dosage, temperature, oxidation system, and different types of catalysts), not to mention its great ability in reusability with 96% of effectiveness after five runs. Moreover, the CODS mechanism is proposed, and based on the obtained results, the kinetics were in agreement with the pseudo‐first‐order model. Based on the obtained incomparable results, it could be considered as an effective, industrial‐scale, and green nanocatalyst for the desulfurization of refractory sulfur compounds in extremely mild conditions.

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