THE SURFACE EMG ACTIVITY ANALYSIS BETWEEN BADMINTON SMASH AND JUMP SMASH

Badminton smash is one of the most powerful techniques among all the racket sports. It may divide into smash and jump smash. The purpose of this study was to analyze the surface EMG activity of upper extremities between smash and jump smash by eight Taiwan elite badminton players. We used two digital video cameras to obtain the 3D kinematics data of shuttlecock, and measured the surface EMG signals of seven upper limb muscles. The results showed that there was no significant difference between the two smashes in initial shuttle velocity. Though the movements of the two smashes were similar, there were significant difference between the two smashes in the sequence of the surface EMG activity of the upper limb and the mean IEMG amplitude in a few muscles. We found that the jump smash exerted the higher EMG activity than smash in the phase before contact point

THE SURFACE EMG ACTIVITY OF THE UPPER LIMB MUSCLES OF BADMINTON FOREHAND AND BACKHAND SMASHES

The purpose of this study was to analyze the surface EMG activity of the upper limb muscles of Taiwan elite badminton players when they were performing the forehand and the backhand smashes. We used two digital video cameras to obtain the 3D kinematics data of the shuttlecock, and measured the surface EMG signals of seven upper limb muscles. The results showed that there were significant differences between forehand and backhand smashes in the following variables: the initial shuttle velocity, the contact height, the initial flight angle of the shuttle, the sequence of the surface EMG activities of the upper limbs and the mean IEMG amplitude in the selected muscles. The reason why the forehand smash was faster than the backhand smash might be because the up swing displacement and up swing racket velocity of the forehand smash was greater than that of the backhand smash

Differential change in cortical and hippocampal monoamines, and behavioral patterns in streptozotocin-induced type 1 diabetes rats

Objective(s): Diabetes mellitus (DM) is a widespread metabolic disorder worldwide. Clinical physicians have found diabetic patients have mild to middle cognitive dysfunction and an alteration of brain monoaminergic function. This study explored the change in various patterns of behavioral models and brain monoamine function under streptozotocin (STZ)-induced type 1 diabetes.Materials and Methods: We established a type 1 DM model via intravenous injection with STZ (65 mg/kg) in rats. Three weeks after the STZ injection, various behavioral measurements including the inhibitory avoidance test, active avoidance test and Morris water maze were conducted. Finally, all rats were dissected and the concentrations of monoamines and their metabolites in cortex and hippocampus were measured by high performance liquid chromatography with electrochemical detection.Results: We found that STZ induced type 1 diabetes (hyperglycemia and lack of insulin) in rats. STZ-induced diabetic rats had cognitive impairment in acquisition sessions and long-term retention of the active avoidance test. STZ-induced diabetic rats also had cognitive impairment in spatial learning, reference and working memory of the Morris water maze. STZ significantly reduced concentrations of norepinephrine (NE) in the cortex and dopamine (DA) in the hippocampus, but increased concentrations of DA and serotonin (5-HT) in the cortex 35 days after injection. The concentration of 5-HT in the hippocampus was also significantly increased.Conclusion: The data suggested that this cognitive impairment after a short-term period of STZ injection might be related to cortical NE dysfunction, differential alteration of cortical and hippocampal DA function, and brain 5-HT hyperfunction

Down-regulation of PKCζ in renal cell carcinoma and its clinicopathological implications

<p>Abstract</p> <p>Background</p> <p>Metastatic renal cell carcinoma (RCC) is highly resistant to systemic chemotherapy. Unfortunately, nearly all patients die of the metastatic and chemoresistant RCC. Recent studies have shown the atypical PKCζ is an important regulator of tumorigenesis. However, the correlation between PKC<b>ζ </b>expression and the clinical outcome in RCC patients is unclear. We examined the level of PKCζ expression in human RCC.</p> <p>Methods</p> <p>PKCζ mRNA and protein expressions were examined by real-time polymerase chain reaction (PCR) and immunohistochemistry (IHC) respectively in RCC tissues of 144 patients. Cellular cytotoxicity and proliferation were assessed by MTT.</p> <p>Results</p> <p>PKCζ expression was significantly higher in normal than in cancerous tissues (<it>P </it>< 0.0001) by real-time PCR and IHC. Similarly, PKCζ expression was down-regulated in four renal cancer cell lines compared to immortalized benign renal tubular cells. Interestingly, an increase of PKCζ expression was associated with the elevated tumor grade (<it>P </it>= 0.04), but no such association was found in TNM stage (<it>P </it>= 0.13). Tumors with higher PKCζ expression were associated with tumor size (<it>P </it>= 0.048). Expression of higher PKCζ found a poor survival in patients with high tumor grade. Down-regulation of PKCζ showed the significant chemoresistance in RCC cell lines. Inactivation of PKCζ expression enhanced cellular resistance to cisplatin and paclitaxel, and proliferation in HK-2 cells by specific PKC<b>ζ </b>siRNA and inhibitor.</p> <p>Conclusions</p> <p>PKCζ expression was associated with tumorigenesis and chemoresistance in RCC.</p

3D Geometrical Inspection of Complex Geometry Parts Using a Novel Laser Triangulation Sensor and a Robot

This article discusses different non contact 3D measuring strategies and presents a model for measuring complex geometry parts, manipulated through a robot arm, using a novel vision system consisting of a laser triangulation sensor and a motorized linear stage. First, the geometric model incorporating an automatic simple module for long term stability improvement will be outlined in the article. The new method used in the automatic module allows the sensor set up, including the motorized linear stage, for the scanning avoiding external measurement devices. In the measurement model the robot is just a positioning of parts with high repeatability. Its position and orientation data are not used for the measurement and therefore it is not directly “coupled” as an active component in the model. The function of the robot is to present the various surfaces of the workpiece along the measurement range of the vision system, which is responsible for the measurement. Thus, the whole system is not affected by the robot own errors following a trajectory, except those due to the lack of static repeatability. For the indirect link between the vision system and the robot, the original model developed needs only one first piece measuring as a “zero” or master piece, known by its accurate measurement using, for example, a Coordinate Measurement Machine. The strategy proposed presents a different approach to traditional laser triangulation systems on board the robot in order to improve the measurement accuracy, and several important cues for self-recalibration are explored using only a master piece. Experimental results are also presented to demonstrate the technique and the final 3D measurement accuracy