In this study, we designed and fabricated an AC magnetic field (ACMF) stimulation bio-reactor for a three-dimensional (3D) culture of nerve cells using a collagen gel as a scaffold. Recently, the use of electromagnetic stimulation to enhance nerve axonal extension has attracted significant attention in nerve regeneration. Thus, we designed a novel 3D bio-reactor that can apply ACMF stimulation to nerve cells with a uniform magnetic flux density. We evaluated the morphology of PC12 cells and primary cells derived from the rat cerebral cortex using a multi photon microscope (MPM) and evaluated the effect of ACMF stimulation on axogenesis and nerve axonal extension. First, an ACMF stimulation bio-reactor was designed using a pole-piece structure. We examined the uniformity of the magnetic flux density generated in the 3D culture region of the bio-reactor using the 3D electromagnetic field finite element analyses. Second, we evaluated the effect of ACMF stimulation in enhancing PC12 cells axonal extension. Cells were disseminated into a collagen gel which was poured into a fabricated culture dish. We observed an increase in the axogenesis ratio and axonal extension length of PC12 cells during the later growth stages under ACMF stimulation. Finally, we confirmed that primary cells with enhanced axonal extension became more susceptible to ACMF stimulation as the intercellular distance increased.

Electromyostimulation is a nonpharmacological prevention method for osteoporosis that is safe and feasible for the elderly and people with physical disabilities. Our previous study demonstrated that random pulse train (RdPT) electromyostimulation of rat quadriceps induces an increase in the mechanical properties of the contralateral unstimulated femoral neck. However, the efficacy of this stimulation on other untested bones is still unclear. The objective of this research is to investigate the response of previously unstimulated bones to single-site electromyostimulation. The left quadriceps of rats were stimulated electrically by periodic pulse train (PrPT) or RdPT with 2 mA-magnitude pulses at 552 μs and a 50% duty ratio. The stimulation effect was examined on the diaphysis of long bones and lumbar vertebrae (L2–L5) by quasi-static mechanical tests and microcomputed tomography analysis. RdPT increased the strain energy at the stimulated left femur but did not change the properties of the other long bones. For the lumber vertebrae, on the other hand, both stimulations showed similar results. The stiffness of lumbar vertebra increased in L2, and the stiffness and the maximum load decreased in L4. Additionally, the BMC (bone mineral content), BV (bone volume), and TV (tissue volume) were reduced in L2, but not changed in L4. The other vertebrae were not affected by the stimulations. In conclusion, RdPT influences not only the stimulated femur, but also the lumbar vertebrae site-dependently as well as PrPT. These findings suggest the whole-body scale effect of electromyostimulation, however, which is not positive in all the bones, requiring further investigations for its clinical applications.

This paper aims to optimize the dexterity and best preoperative position of single-hole laparoscopic surgery (SHLS) robot in laparoscopic surgery. A 5DOF SHLS robot was designed with a series-parallel hybrid structure, and the inverse kinematics equation and Jacobian matrix of the SHLS robot were derived, together with the positioning workspace. Then, The dexterity of the SILS robot was analyzed by the conditional number of Jacobian matrix. For the preoperative position, the original gradient projection method was described theoretically, the minimum distance between endoscope end and lesion was taken the objective function, and the position planning based on gradient projection method was used to establish a planning model for the end endoscope position of the robot. And, the optimal position planning based on gradient projection algorithm was applied to the preoperative positioning analysis of the SHLS robot and the MATLAB software was used to simulate position planning. The simulation results further testify that the feasibility and correctness of the workspace, dexterity and positioning plan of SHLS robot, and validates that the SILS robot has a reasonable workspace, sufficient dexterity and optimal position planning to meet the needs of single-incision laparoscopic surgery.

An ampoule is a glass cylinder that contains intravenous solutions. Ampoule opening (AO) is performed by nurses on a daily basis, but the procedure involved can cause injuries to the hand as well as contamination of ampoule contents with glass microparticles. As it is currently impossible to completely eliminate the use of glass ampoules, one should learn how to safely perform the AO operation. Herein, we quantitatively analyze the combined seven upper-limb movements of ten experienced participants to clarify the mechanism of AO operations and establish a procedure for safe AO. Unlike current instruction manuals, this study focuses on the joint movements of dominant and nondominant upper limbs rather than on finger positions. A motion-capture system and video cameras are used to analyze the above seven movements of each upper limb. Based on results obtained, the following three guidelines for performing AO operations are derived: (1) supinate the elbow joint to break the ampoule neck; (2) move the dominant hand away from the cutting plane of the ampoule immediately after ampoule breaking without moving the nondominant hand to avoid unnecessary contact of fingers with the cutting plane; (3) synchronize elbow-joint extension with supination in step (1) as the dominant hand is moved away after ampoule breaking. This approach not only ensures safe AO but also helps in learning other skills related to technical nursing education.