Comparison of different thromboembolism risk scores with the predictive value of left atrial thrombosis and/or spontaneous ultrasound in patients with non-valvular atrial fibrillation

Objective: To compare the predictive value of CHADS2, CHA2DS2-VASc, ATRIA and R2-CHADS2 scores and left atrial thrombosis and/or spontaneous ultrasound in patients with non-valvular atrial fibrillation (AF) Methods patients with non-valvular atrial fibrillation who were hospitalized in the Department of Cardiology of Sun Yat Sen Memorial. Results: 564 patients were included. The age of patients was (61.1 ± 10.1) years old, of which 63.3% were men. Hypertension was the most common complication, which was found in 49.6% of patients. Patients were divided into thrombus group (n = 82) and non-thrombus group (n = 482) according to the presence of left atrial thrombus and/or spontaneous ultrasound development CHADS2 score in thrombotic group (1[0,2]) was higher than that in non-thrombotic group (1[0,1]) (P < 0.05), and CHA2DS2-VASc score in thrombotic group (2[1,3]) was higher than that in non-thrombotic group (2[1,2]) (P < 0.05) 11.06%, 13.39%, 26.58%, 18.52% and 16.67% of patients with CHADS2 score of 0, 1, 2, 3 and 4 had left atrial thrombus and/or spontaneous ultrasound (P fortrend = 0.016), and 11.06%, 13.39% and 23.68% of patients with low, medium and high risk had left atrial thrombus and/or spontaneous ultrasound (P fortrend = 0.004); 10.81%, 10.19%, 16.57%, 21.05%, 21.05%, 16.67%, 14.29% of patients with CHA2DS2-VASc score of 0, 1, 2, 3, 4, 5, 6 or above had left atrial thrombosis and/or spontaneous ultrasound development (P fortrend = 0.019), and 8.75%, 13.90% and 19.35% of patients with low, medium and high risk had left atrial thrombosis and/or spontaneous ultrasound development (P fortrend = 0.004); The area under the ROC curve of ATRIA score and R2-CHADS2 score was 0.562. The samples based on this study had no statistical significance in the diagnosis of left atrial thrombosis and/or spontaneous ultrasound (P>0.05). Conclusion: CHADS2 score and CHA2DS2-VASc score have considerable and limited diagnostic value for left atrial thrombosis and/or spontaneous ultrasound in patients with non-valvular atrial fibrillation

Impact of biodiesel fuel on cold starting of automotive direct injection diesel engines

The use of biodiesel fuels in diesel engines is gaining attention as a promising solution to control CO2 emissions. Great research efforts have been carried out to identify the impact of biodiesel physical and chemical properties on engine systems and processes. Most of these investigations were performed in warm conditions, but the suitability of biodiesel for starting the engine at under-zero ambient temperatures has not widely evaluated. The surface tension and the viscosity of biodiesel fuels are higher compared to those of standard diesel and, in cold conditions, these differences become critical since the injection fuel rate is largely affected and consequently the combustion process can be deteriorated. In order to improve its flow characteristics at cold temperatures and make them more suitable for low temperatures operation, additives are used in biodiesel fuels. In this paper the suitability of different biodiesel fuels, with and without additives, for cold starting of DI (direct injection) diesel engines has been evaluated. The results have shown that the engine start-ability with pure biodiesel fuels can be largely deteriorated. However, using diesel/biodiesel blends the start-ability of the engine can be recovered with the additional benefit of reducing the opacity peak of the exhaust gasesBroatch Jacobi, JA.; Tormos Martínez, BV.; Olmeda González, PC.; Novella Rosa, R. (2014). Impact of biodiesel fuel on cold starting of automotive direct injection diesel engines. Energy. 73:653-660. doi:10.1016/j.energy.2014.06.062S6536607