Safety of short-term dual antiplatelet therapy after drug-eluting stents:An updated meta-analysis with direct and adjusted indirect comparison of randomized control trials

Background: Duration of dual antiplatelet therapy (DAPT) following drug-eluting stents (DES) remains controversial and is a topic of ongoing research. Methods: Direct and adjusted indirect comparisons of all the recent randomized control trials (RCTs) were performed to evaluate the safety of short-term versus long-term DAPT following DES. Results: 8 RCTs were identified and 7 (16,318 subjects) were included. 4 groups of 3 vs 12 months, 6 vs 12 months, 6 vs 24 months and 12 vs 24 months of DAPT were used for direct comparison. There was no significant difference in stent thrombosis, myocardial infarction (MI), stroke and revascularization, cardiovascular and all-cause mortality between the different durations in all 4 groups. Pooling trials of 3–6 months of DAPT against 12 months, we found a significant reduction in the risk of total bleeding (RR 0.61, 95% CI 0.43–0.87). Adjusted indirect comparison between 3 vs 6 months, 3 vs 24 months and 6 vs 24 month duration of DAPT showed no significant differences in risk of death or MI, or revascularization between 3 or 6 months and 24 months. However, 24 months of DAPT was associated with significantly more bleeding than 3 or 6 months. Conclusions: 3 to 6 months of DAPT following second generation DES and above is safe with no increased risk of thrombotic complications and mortality, and lower bleeding risk. However a tailored approach may be more appropriate for high-risk patients. Keywords: Percutaneous coronary intervention; Drug-eluting stent; Acute coronary syndrome; Dual antiplatelet treatment; Duration of therap

Breaking an image encryption algorithm based on chaos

Recently, a chaos-based image encryption algorithm called MCKBA (Modified Chaotic-Key Based Algorithm) was proposed. This paper analyzes the security of MCKBA and finds that it can be broken with a differential attack, which requires only four chosen plain-images. Performance of the attack is verified by experimental results. In addition, some defects of MCKBA, including insensitivity with respect to changes of plain-image/secret key, are reported.Comment: 10 pages, 4 figure

A haptic base human robot interaction approach for robotic grit blasting

This paper proposes a remote operation method for a robot arm in a complex environment by using the Virtual Force (VF) based approach. A virtual robot arm is manipulated by a steering force, at the end-effecter, which is generated according to the movement of a feedback haptic. A three-dimensional force field (3D-F2) is employed in collision detection and avoidance. Repulsive forces from the 3D-F2 are produced and feedback to the haptic device that enables the operator to have a sense of touch on the encountered obstacle and then steer the arm to avoid it. As a result, collision-free poses of the virtual robot arm can then be used to command the real robot. Experiments are conducted in a mock up bridge environment where the real robot arm is steered to target points by the operator. Experiment results have shown successful collision avoidance and emulation of the actual command force and the virtual forces in remote operations