THE KINEMATICS CHAIN OF INSTEP KICKING OF SOCCER WITH UPPERBODY CONSTRAINED: A PILOT STUDY

The purpose of this study was to understand the kicking performance when the upperbody motion has been limited. One player in the college cup level A volunteered to participate in this study (Aged: 20 years, Height: 172 cm, Body mass: 65 kg). A VICON motion capture system (200 Hz) was used to capture the kicking motion. The participant was asked to kick the ball both using an arm swing and not using an arm swing. The Visual3D was used to calculate the segment velocity, angular velocity, and kinetic chain. The results indicated that kicking with arm swing had a greater ball and lower-extrimity segment velocity. The main effect for lower ball velocity during kicking without arm swing is the decreased angular velocity at the ankle joint. When arm motion has been limited, players should noticed that the ankle joint needs to follow through after foot-ball contact

KINEMATICS OF SOCCER DRIBBLING IN DIFFERENT TASKS

The purpose of this study was to find the differences in kinematics between different speeds and cutting directions. Ten male university division 1 soccer players served as the subjects in this study. The Vicon Motion System and the KISTLER force platform were used synchronously to collect data. The length of projection vector was normalized by leg length. 2way ANOVA was used for statistics. Simple main effect was tested if no significant interaction effect was noted. The significant level was set as .05. The length of projection vector between COM and the heel of pivot leg onto X-Y plane in high speed tasks were longer than that in low speed tasks (p \u3c .05). The angle between the X axis and the projection vector between COM and the heel of pivot leg onto X-Y plane had significant interaction effect (p \u3c .05). In low speed tasks, players’ pivot legs landed more laterally and that might enhance lateral motion of body, especially when players cut to the dominate side (right). It was concluded that players would change their cutting tactics at different speeds and in different directions. Landing position of pivot leg might be a factor that would help defender to know the cutting side of attacker at low dribbling speed

THE ELECTROMYOGRAPHY CHARACTERISTICS BETWEEN DIFFERENT LEVELS OF SOCCER PLAYER ON INSTEP KICKING

This study improves kicking performance by comparing muscle activity between different levels of players. Twelve soccer players in the college cup in division I and division II volunteered to participate in this study. A VlCON motion capture system (200 Hz) was used to capture the kicking motion including back-swing and forward-swing. The Noraxon electromyography system was used to collect and analyze the percentage of maximum voluntary contraction on rectus femoris, bicepsfemoris, tibialis anterior, and gastrocnemius. The Mann-Whilney U (a = -05) test was applied to assess significant differences in this study. The results indicated that division II players had a greater percentage maximum voluntary contraction in tibialis anterior in the back-swing. To avoid stiff movements in soccer kicks, division II players should decrease muscle contraction in the tiblalis anterior In the back-swing

CALIBRATION OF PRESSURE SENSORS FOR HAND GRIP MEASUREMENT

The purpose of this study was to assess the accuracy of grip force sensors. Methods: Several standard weights were used to calibrate the grip sensor in the static condition, The descriptive statistics and linear regression were used to present the accuracy and errors. Results: Results of this study showed a high level of sensing areas linear relationship under static loading. Conclusion: Data from this study showed high accuracy of the pressure sensor. The pressure sensor could te used for hand grip measurement

Metrology Camera System of Prime Focus Spectrograph for Subaru Telescope

The Prime Focus Spectrograph (PFS) is a new optical/near-infrared multi-fiber spectrograph designed for the prime focus of the 8.2m Subaru telescope. PFS will cover a 1.3 degree diameter field with 2394 fibers to complement the imaging capabilities of Hyper SuprimeCam. To retain high throughput, the final positioning accuracy between the fibers and observing targets of PFS is required to be less than 10um. The metrology camera system (MCS) serves as the optical encoder of the fiber motors for the configuring of fibers. MCS provides the fiber positions within a 5um error over the 45 cm focal plane. The information from MCS will be fed into the fiber positioner control system for the closed loop control. MCS will be located at the Cassegrain focus of Subaru telescope in order to to cover the whole focal plane with one 50M pixel Canon CMOS camera. It is a 380mm Schmidt type telescope which generates a uniform spot size with a 10 micron FWHM across the field for reasonable sampling of PSF. Carbon fiber tubes are used to provide a stable structure over the operating conditions without focus adjustments. The CMOS sensor can be read in 0.8s to reduce the overhead for the fiber configuration. The positions of all fibers can be obtained within 0.5s after the readout of the frame. This enables the overall fiber configuration to be less than 2 minutes. MCS will be installed inside a standard Subaru Cassgrain Box. All components that generate heat are located inside a glycol cooled cabinet to reduce the possible image motion due to heat. The optics and camera for MCS have been delivered and tested. The mechanical parts and supporting structure are ready as of spring 2016. The integration of MCS will start in the summer of 2016.Comment: 11 pages, 15 figures. SPIE proceeding. arXiv admin note: text overlap with arXiv:1408.287

RNA interference of argininosuccinate synthetase restores sensitivity to recombinant arginine deiminase (rADI) in resistant cancer cells

Background Sensitivity of cancer cells to recombinant arginine deiminase (rADI) depends on expression of argininosuccinate synthetase (AS), a rate- limiting enzyme in synthesis of arginine from citrulline. To understand the efficiency of RNA interfering of AS in sensitizing the resistant cancer cells to rADI, the down regulation of AS transiently and permanently were performed in vitro, respectively. Methods We studied the use of down-regulation of this enzyme by RNA interference in three human cancer cell lines (A375, HeLa, and MCF-7) as a way to restore sensitivity to rADI in resistant cells. The expression of AS at levels of mRNA and protein was determined to understand the effect of RNA interference. Cell viability, cell cycle, and possible mechanism of the restore sensitivity of AS RNA interference in rADI treated cancer cells were evaluated. Results AS DNA was present in all cancer cell lines studied, however, the expression of this enzyme at the mRNA and protein level was different. In two rADI-resistant cell lines, one with endogenous AS expression (MCF-7 cells) and one with induced AS expression (HeLa cells), AS small interference RNA (siRNA) inhibited 37-46% of the expression of AS in MCF- 7 cells. ASsiRNA did not affect cell viability in MCF-7 which may be due to the certain amount of residual AS protein. In contrast, ASsiRNA down- regulated almost all AS expression in HeLa cells and caused cell death after rADI treatment. Permanently down-regulated AS expression by short hairpin RNA (shRNA) made MCF-7 cells become sensitive to rADI via the inhibition of 4E-BP1-regulated mTOR signaling pathway. Conclusions Our results demonstrate that rADI-resistance can be altered via AS RNA interference. Although transient enzyme down- regulation (siRNA) did not affect cell viability in MCF-7 cells, permanent down- regulation (shRNA) overcame the problem of rADI-resistance due to the more efficiency in AS silencing

Metrology Camera System of Prime Focus Spectrograph for Subaru Telescope

The Prime Focus Spectrograph (PFS) is a new optical/near-infrared multi-fiber spectrograph designed for the prime focus of the 8.2m Subaru telescope. The metrology camera system of PFS serves as the optical encoder of the COBRA fiber motors for the configuring of fibers. The 380mm diameter aperture metrology camera will locate at the Cassegrain focus of Subaru telescope to cover the whole focal plane with one 50M pixel Canon CMOS sensor. The metrology camera is designed to provide the fiber position information within 5{\mu}m error over the 45cm focal plane. The positions of all fibers can be obtained within 1s after the exposure is finished. This enables the overall fiber configuration to be less than 2 minutes.Comment: 10 pages, 12 figures, SPIE Astronomical Telescopes and Instrumentation 201