Abstract: A left atrial appendage (LAA) occluder and an LAA occlusion system are disclosed. The LAA occluder enables an increased surgical success rate by allowing repeated good positioning, retrieval and release of the occluder and avoiding the problem of entanglement of the occluding stent during surgery. The LAA occluder includes an occluding stent, a proximal securing member a distal securing member. The occluding stent includes an occlusion structure and a traction structure. The delivery device includes a hollow push tube and a control shaft. The distal securing member can be driven by the control shaft to move toward the proximal securing member until a first distal end of the occlusion structure is in a collapsed configuration, where the distal securing member is blocked from further movement, avoiding the problem of entanglement arising from inward rolling of the occluding stent in the vent of human error.

Abstract: Methods of and systems for generating a bio-fuel from a bio-substance with the assistance of radio frequency heating are taught. In some embodiments, the system includes a reactant containing a bio-substance and an alcohol, a catalyst to be mixed with the reactant, and a radio frequency wave generator for generating a radio frequency wave to be applied to the bio-substance. The bio-substance comes from any appropriate sources including animal oils and fats, such as beef tallow. Alternatively, the bio-substance is able to come from a plant, a fungus, or a protist. One example would be canola oil. In some embodiments, the catalyst is a transesterification catalyst, a Lewis acid, or a Lewis base such as sodium hydroxide. In some embodiments, the alcohol is methanol. In some embodiments, the bio-fuel is bio-diesel.