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Genetic mechanism behind aging rate uncovered.

China launches survey of endangered porpoises in Yangtze River.

Academic institutes and companies join forces to boost precision nutrition research.

Gigantic DNA database to be built in Nanjing.

Home test kit for cervical screening developed by BGI.

Chinese HPV vaccine gets permission for clinical testing.

Ineffective baby vaccines by two companies recalled.

Robot scores high result on national doctor qualification test.

Head transplant ‘never’ to be allowed.

China ranks second in Global Science Innovation.

Veolia to support Danone Nutricia Wuxi plant in China.

Chinese drug delivery devices market to reach USD638.4 million by 2023.

In this paper, a prototype of a robotic system for accurate and consistent insertion of a percutaneous biopsy needle into the prostate is presented. A transrectal ultrasound (TRUS) probe is used to collect a series of two-dimensional (2D) images of the prostate. These images are used to create a 3D computer model of the organ which is used by the urologist to define the biopsy points within the prostate. The robotic system then calculates the required trajectory of the needle, which can be simulated on the computer. Following this, the robot is configured accordingly and the actual biopsy is performed. Cadaveric and human trials have validated the robot's needle placement error to be less than 2.5 mm. Our future work includes the integration of a cancer predictive modality into the system to increase the cancer detection rate. The robotic system could also be modified to accurately place foreign bodies into the prostate, which could improve therapeutic procedures such as Brachytherapy.

Steerable needles hold the promise of improving the accuracy of both therapies and biopsies as they are able to steer to a target location around obstructions, correct for disturbances, and account for movement of internal organs. However, their ability to make late-insertion corrections has always been limited by the lower bound on the attainable radius of curvature. This paper presents a new class of steerable needle insertion where the objective is to first control the direction of tissue fracture with an inner stylet and later follow with the hollow needle. This method is shown to be able to achieve radius of curvature as low as 6.9mm across a range of tissue stiffnesses and the radius of curvature is controllable from the lower bound up to a near infinite radius of curvature based on the stylet/needle step size. The approach of “fracture-directed” steerable needles indicates the promise of the technique for providing a tissue-agnostic method of achieving high steerability that can account for variability in tissues during a typical procedure and achieve radii of curvature unattainable through current bevel-tipped techniques. A variety of inner stylet geometries are investigated using tissue phantoms with multiple stiffnesses and discrete-step kinematic models of motion are derived heuristically from the experiments. The key finding presented is that it is the geometry of the stylet and the tuning of the bending stiffnesses of both the stylet and the tube, relative to the stiffness of the tissue, that allow for such small radius of curvature even in very soft tissues.

The kinematic relationship between the needle base and the robot's joints is analyzed. The analysis process is based on the aided needle-insertion robot built by our group. The thinking of needle-inserting procedure is confirming the needle base's posture before the needle inserted into tissue. The method of Denavit-Hartenberg (D-H) parameters is used to establish a link robot body-frames with the structural characteristics of the robot. After analysing kinematics, the kinematics equation is presented. The kinematics inverse solutions are obtained with the analytical method and geometry analysis method.