Techniques for mitigating interference in an asynchronous wireless network are described. The cover comprises an upper housing, a base housing, a glass, a first rubber ring, a second rubber ring and four shockproof elements. The time varying path may be circular, as to obtain a helical or spiral flow pattern or non-circular as to obtain, for example, a zig-zagging or figure eight pattern. Also provided is a related method for repairing an intervertebral disc by using such a system to deliver and cure the biomaterial in situ. The method includes forming a thixotropic cement slurry downhole, including mixing the cement slurry and the thixotropic agent downhole.