Salticids are diurnal hunters known for acute vision, remarkable predatory strategies and jumping ability. Like other jumpers, they strive for stability and smooth landings. Instead of using inertia from swinging appendages or aerodynamic forces by flapping wings as in other organisms, we show that salticids use a different mechanism for in-air stability by using dragline silk, which was previously believed to function solely as a safety line. Analyses from highspeed images of jumps by the salticid Hasarius adansoni demonstrate that despite being subject to rearward pitch at take-off, spiders with dragline silk can change body orientation in the air. Instantaneous drag and silk forces calculated from kinematic data further suggest a comparable contribution to deceleration and energy dissipation, and reveal that adjustments by the spider to the silk force can reverse its body pitch for a predictable and optimal landing. Without silk, upright-landing spiders would slip or even tumble, deferring completion of landing. Thus, for salticids, dragline silk is critical for dynamic stability and prey-capture efficiency. The dynamic functioning of dragline silk revealed in this study can advance the understanding of silk's physiological control over material properties and its significance to spider ecology and evolution, and also provide inspiration for future manoeuvrable robot designs.

Pulse wave velocity (PWV) is the most popular index to assessment the arterial stiffness. Currently, several non-invasive examination methods with single channel for PWV are announced. This paper proposes a non-invasive digital volume pulse (DVP) measuring system using a dual channel simultaneous measurement method try to meet the demands for home healthcare equipment which is easy to operate. Through synchronal technical in measuring DVP signals from finger and toe can achieves more precise time and substantially reduces the time spend in measurement procedures. In the other side, the proposed system developed an algorithm to locate the "Foot of the wave" without facilitating of electrocardiogram (ECG).