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Coronary artery disease (CAD) has become one of the important causes of human death, and coronary stent implantation is one of the most effective methods for the treatment of CAD. But the current clinical treatment has a high long-term restenosis rate and is easy to form late stent thrombosis. In order to solve these problems, coronary artery stent surface was directly modified by laser interference lithography and the highly ordered concave structures were fabricated. The morphology and contact angle (CA) of the microstructure were measured with scanning electron microscopy (SEM) and CA system. The water repellent property of the stent was also evaluated by the method of contacting the water drop with the stent and then separating. The result showed that the close-packed concave structure with the period of about 12.194 μm can be fabricated on the stent surface under special parameters (laser energy density of 3.5 J/cm, incident angles of 3°, exposure time of 80 s) by the three-beam laser interference of 1064 nm and the form structure has good water repellency with contact angle of 120°.

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To solve the problems with coronary stent implantation, coronary artery stent surface was directly modified by three-beam laser interference lithography through imitating the water-repellent surface of lotus leaf, and uniform micro-nano structures with the controllable period were fabricated. The morphological properties and contact angle (CA) of the microstructure were measured by scanning electron microscope (SEM) and CA system. The water repellency of stent was also evaluated by the contact and then separation between the water drop and the stent. The results show that the close-packed concave structure with the period of about 12 µm can be fabricated on the stent surface with special parameters (incident angle of 3°, laser energy density of 2.2 J·cm -2 and exposure time of 80 s) by using the three-beam laser at 1 064 nm, and the structure has good water repellency with CA of 120°.The coronary artery stent implantation has become the first choice for the treatment of coronary heart disease (CHD) in the world currently. Although the equipment and medication are increasingly improved, in-stent restenosis (ISR) is still a major defect of stent implantation [1] . Due to the occurrence of restenosis, still more than 15% patients with coronary stent implantation will accept interventional therapy in a year [2] . Therefore, it is of great significance to develop a new type of coronary stent, which has low restenosis rate and can prevent late stent thrombosis. In recent years, the studies show that the biocompatibility of the materials could be increased by the biomimetic process of surface and coating [3][4][5][6][7][8] . Consequently, the preparing bionic surface with regular geometric structure is beneficial to the rapid, directional and orderly adhesion and the growth of endothelial cells, which can reduce the formation of restenosis and late thrombosis.Laser interference lithography (LIL) has been applied in many fields, such as solar cells [9,10] , nano-scale patterned sapphire substrate [11] and bionics [12,13] . And studies have shown that the minimum feature size of direct LIL can reach 27 nm (laser wavelength of 308 nm, pulse width no more than 10 ns) [14] , which can fully meet the requirements of the process in this paper. Compared with other approaches, such as electron beam lithography, ion beam lithography and scanning probe lithography, which adopt the point by point writing strategy [15,16] , LIL reduces the required processing time by using multi-beam simultaneously. In addition, the long focal depth and the maskless process of LIL lower the flatness requirements of substrate and can realize imaging on a non-planar surface without affecting the resolution and image contrast.In this paper, LIL is used to modify the surface of coronary stent by imitating the water-repellent surface of lotus leaf. Test results show that the processed stent has good water repellency, which can achieve the desired effects.LIL is very suitable to process the coronary stent with the structure of mesh tubes, as shown in Fig....

Most people with Autism Spectrum Disorder (ASD) experience atypical sensory modality and need help to self-regulate their sensory responses. Results of a pilot study are presented here where temperature, noise types and noise levels are used as independent variables. Attention-based tests (ABTs), Electrodermal Activity (EDA) and Electroencephalography (EEG) sensors are used as dependent variables to quantify the effects of temperature and noise. Based on the outcome of the analyses, it is feasible to use off-the-shelf sensors to recognize physiological changes, indicating a possibility to develop sensory management recommendation interventions to support people with ASD.