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ObjectiveTo observe the effect of autologous bone marrow-derived mesenchymal stem cells (BMMSCs) on the portal hemodynamics in patients with hepatitis B virus (HBV)-related decompensated cirrhosis. Methods Forty-six patients with HBV-related decompensated cirrhosis, who were admitted to the hospital from February 2011 to January 2012, were divided into treatment group (n=23) and control group (n=23). There were no significant differences in sex, age, diagnosis, biochemical parameters, and imaging findings between the two groups. All patients provided informed consent prior to treatment. Both groups received antiviral, liver-protecting, and diuretic treatment. In addition, in the treatment group, bone marrow (200 ml) was drawn from each patient, BMMSCs were isolated, purified, and cultured, and the cultured cells were processed into cell suspension (10 ml); the cell suspension was injected into the liver via the hepatic artery. After 8 and 12 weeks of treatment, the changes in portal hemodynamic parameters were evaluated. The obtained data were analyzed using SPSS 13.0 software; the paired t test was used for within-group comparisons. ResultsAfter 8 and 12 weeks of treatment, in the treatment group, the diameter of portal vein (DPV) was significantly decreased to 13.26±1.31 mm (t=2.290, P＜0.05) and 12.83±138 mm (t=3.421, P＜0.01), and the diameter of splenic vein (DSV) was significantly decreased to 8.39±1.38 mm (t=2.079, P＜0.05) and 8.02±1.24 mm (t=2.787, P＜0.01); compared with the control group, the treatment group had significantly lower DPV (t=2.382, P＜0.05; t=2.602, P＜0.05) and DSV (t=3.236, P＜0.01; t=4.185, P＜0.01). After 8 and 12 weeks of treatment, in the treatment group, the portal vein maximum velocity (PVX) was significantly increased to 2072±463 cm/s (t=2.833, P＜0.01) and 2058±346 cm/s (t=3.198, P＜0.01); compared with the control group, the treatment group had significantly higher PVX (t=2.530, P＜0.05; t=3.123, P＜0.01). ConclusionAutologous BMMSCs can significantly improve the portal hemodynamics in patients with HBV-related decompensated cirrhosis.

This paper developed a new structural configuration of tilt tri-rotor UAV. Based on the establishment of the coordinate system, the force in the helicopter mode was analyzed and the nonlinear six-degree-of-freedom equation of the aircraft was obtained. Finally, the model was established and the simulation of the open loop system was carried out.

The human body is a spring-mass-damper system that oscillates up and down while moving. Wearable robots can add energy to the person at an appropriate time to enhance human moving performance and reduce the metabolic cost of performing cyclic tasks simultaneously. We have developed a phase oscillator to add assisted power at resonance so the system attains suitable energy to overcome the vertical resistance. The oscillator is robust to disturbances and initial conditions and allows wearable robots to enhance running, reduce metabolic cost, and increase hop height. Results show that when the external force is angled at 25 degrees, the phase oscillator can maintain robust bounded energy in a limit cycle to enhance human running performance.

A controllable two-way self-locking mechanism was developed in this paper to improve the tractive ability of inchworm micro In-pipe robot and reverse its moving direction. Firstly, the robot structure was proposed and its relevant locomotive functions were introduced. Then the mechanism was analyzed and its mathematical model was built to deduce the conditions of direction reversing and diameter variation adapting. Finally a robot prototype was developed based on the results derived above, and its related experiments were carried to test these conditions.

A reconfigurable tracked mobile robot (RTMBot) is presented in this paper based on a parallel four-bar mechanism. Firstly the structure of the robot is introduced. After that a centroid configuration model is proposed to analyze the trench-crossing capability of the robot and plan the locomotion configurations for crossing trenches. Then a virtual robot prototype has been constructed to analyze and simulate the performance of trench-crossing. Finally, a prototype of the reconfigurable tracked mobile robot has been produced, and experiments have been performed to verify the design concept and its embodiment. The results show that RTMBot can reconfigure itself to cross trenches.

Amphibious NDT Robots

By researching the fatigue and durability (F&D) tests of the construction vehicles (CV), the key technologies of the virtual fatigue test such as the virtual prototype modeling for construction vehicles, virtual test, load history acquisition as well as the virtual fatigue life prediction etc. were depicted in detail. Consequently, the overall frame of the virtual fatigue test system was constructed. Finally, the virtual fatigue test system has been realized based on the MSC software according to the frame. Virtual fatigue test based on modal stress recovery (MSR) has been carried out on a construction vehicle within the system for predicting its part's fatigue life. It concludes that this virtual fatigue test system can provide reliable reference for loads history processing of the road simulation test, parts' critical section predicting etc., reducing working intensity of the real vehicle tests.