EFFECTS OF CUSTOM-MADE 3D PRINTED INSOLES FOR FLAT-FOOT PEOPLE ON GAIT PARAMETERS: A PRELIMINARY STUDY

The purpose of this study was to make low-cost and custom-made 3D printed insoles for flat-foot people and to investigate the feasibility of these insoles in walking and running. Thirty people (15 normal and 15 flat-foot people) participated in this study. 3D scanner, 3D printer, and CAD software were used to produce insoles and motion capturing system and a force plate were used to perform gait analysis. Results indicated that custom-made 3D printed insoles were not effective on joint angles and ground reaction forces, but they affected the trajectory of COP positively during stance phase. Further study with different filling rate and materials of insoles are required to generalize 3D printed insoles for flatfoot people

COMPARATIVE ANALYSIS OF YANG HAK-SEON VAULT AND TSUKAHARA 1260? VAULT IN GYMNASTICS

The study was a single-subject study on the top-elite vaulter in the world. This study was purposed to compare kinematic differences between Yang Hak-Seon vault (Yang-1) and Tsukahara 1260? vault (Yang-2) performed by Yang Hak-Seon. Fourteen high-speed cameras were used to capture a whole body segment motion of Yang-2 vault during the practice session. Yang-1 vault showed faster CM vertical velocity until the vault table takeoff and faster CM horizontal velocity prior to the vault table touchdown. However, the trunk rotation angle and its angular velocity of Yang-2 vault exceeded Yang-1 vault significantly. This might be due to a half turn off the springboard onto the vault table of Yang-2 vault, which resulted in larger initial angular momentum at the vault table touchdown and further increase in angular velocity during the vault table contact

DOSE FASTER HOPPING FREQUENCY IMPROVE RESPONSE TIME AND KICKING SPEED IN TAEKWONDO ROUNDHOUSE KICK?

The purpose of this study was to investigate the effect of rhythmic hopping frequency on the response time and kicking speeds in Taekwondo roundhouse kick. Eleven elementary and middle-school athletes voluntarily participated in this study. They performed five roundhouse kicks at three different hopping frequencies (normal, 15% faster than normal, and 15% slower than normal) and no hop condition. Results indicated that the 15% slower hopping frequency induced a significantly longer response time than the 15% faster frequency. The 15% faster frequency resulted in faster maximum kicking speed than normal frequency did, while there was no difference in contact kicking speed. Partially the faster hopping frequency would be beneficial to kicking performance

EFFECTS OF FOOT PLANTING POSITIONS ON KNEE JOINT IN DROP LANDING

The purpose of this study was to investigate the effect of three different foot placement positions at the moment of foot-ground contact on the knee joint kinematics and kinetics in drop landing in an attempt to estimate the risk of non-contact anterior cruciate ligament (ACL) injury. Three foot placement positions were toe-in (TI), neutral (N), and toe-out (TO) positions according to the heading direction of toes relative to femur. Seventeen college students participated in this study and motion capturing system with forceplatforms was used to assess the drop landings. Toe-in (TI) position should be avoided due to the highest combined loading of valgus and internal rotation. The neutral foot landing position is recommended to minimize the risk of non-contact ACL injury

Natural durability of some hardwoods imported into korea for deck boards against decay fungi and subterranean termite in accelerated laboratory tests

This study evaluated the natural durability of seven imported hardwoods (bangkirai, burckella, ipe, jarrah, kempas, malas, and merbau) used for deck boards against decay fungi (Fomitopsis palustris, Gloeophyllum trabeum, Trametes versicolor, and Irpex lacteus) and the subterranean termite (Reticulitermes speratus kyushuensis) in accelerated laboratory tests. Ipe, jarrah, and merbau were very durable to fungal attack, with performance comparable to ACQ-treated wood. Bangkirai, burckella, kempas, and malas were classified as durable or moderately durable, depending on the fungal species tested. All wood species except for merbau were highly resistant to termite attack. Termite resistance was similar to ACQ-treated wood. Merbau showed somewhat less than all other species but still significant termite resistance. These results indicated that selected naturally durable hardwood species could inhibit fungal and termite attacks as effectively as ACQ treatment. The natural durability of wood species tested in this study is most likely due to the biocidal extractive content of the wood

Efficacy and Safety of a Dexamethasone Implant in Patients with Diabetic Macular Edema at Tertiary Centers in Korea

Purpose. To evaluate the real-world efficacy and safety of the dexamethasone implant (DEX implant) in patients with diabetic macular edema (DME). Methods. Retrospective, multicenter, and noncomparative study of DME patients who were treated with at least one DEX implant. A total of 186 eyes from 165 patients were included. Best-corrected visual acuity (BCVA), central retinal thickness (CRT), complications, and number of retreatments were collected. Data at baseline and monthly for 6 months were analyzed. Results. The average baseline BCVA and CRT were 0.60 LogMAR and 491.6 μm, respectively. The mean BCVA improved until 3 months and then decreased up to 6 months of follow-up (0.53, 0.49, and 0.55 LogMAR at 1, 3, and 6 months; p=0.001, <0.001, and 0.044, resp.). The change of mean CRT was similar to BCVA (345.0, 357.7, and 412.5 μm at 1, 3, and 6 months, p<0.001, <0.001, and <0.001, resp.). 91 eyes (48.9%) received additional treatment with anti-VEGF or DEX implant. The average treatment-free interval was 4.4 months. In group analyses, the DEX implant was more effective in pseudophakic eyes, DME with subretinal fluid (SRF), or diffuse type. Conclusions. Intravitreal dexamethasone implants are an effective treatment for patients with DME, most notably in pseudophakic eyes, DME with SRF, or diffuse type. A half of these patients require additional treatment within 6 months

KINEMATIC COMPARISONS OF KETTLEBELL TWO-ARM SWINGS BETWEEN EXPERTS AND BEGINNERS

The purpose of this study was to investigate kinematic comparisons of kettlebell two-arm swings between experts and beginners in order to find out biomechanical key points for preventing sports injuries and enhancing kettlebell performance. Four experts and three beginners performed kettlebell two-arm swings fifteen times with a 16 kg kettlebell. Experts demonstrated larger ranges of motions (ROM) of pelvic segment and hip joint than beginners, while beginners revealed larger ROM of shoulder joint than experts. Magnitudes and sequential orders of peak angular velocities of major joints were significantly different between two groups. Conclusively, the mobility of pelvic segment and hip joint are required, while the stability of the other joint are needed to produce appropriate kettlebell two-arm swings. The activation and strength of gluteus muscles would be key contributors

EFFECTS OF WALKING SPEED AND AGE ON THE DIRECTIONAL STRIDE REGULARJRY AND GAIT VARIABILITY IN TREADMILL WALKING

The purpose of this study was to assess the directional stride regularity (SR) and gait variability (GV) of data from shoe-type inertial measurement unit (IMU) sensors during levelled treadmill walking. The DynaStabtm (IMU based gait analysis system) including Smart Balance' (shoe-type data logger) was used to collect normal gait data from forty-four subjects in their 20s (n=20), 40s (n=13), and 60s (n=ll). Four different walking speeds (3, 4, 5, and 6 km/h, respectively) on a treadmill were applied for one-minute of continuous levelled walking. Only lateral kinematics (mediolateral acceleration and yawing and rolling angular velocities) revealed significant interactions from walking speed and age, demonstrating lower stride regularity and higher gait variability than the anteroposterior and vertical kinematics