편마비 환자의 단하지 보조기 착용유무에 따른 하지 체중지지율과 보행특성의 변화에 관한 연구

김택훈,구애련,김종만 한국전문물리치료학회 1996 한국전문물리치료학회지 Vol.3 No.2

미끄럼 바닥에서 안정성 유지를 위한 균형 전략과 평가방법

김택훈,윤두식 한국전문물리치료학회 2003 한국전문물리치료학회지 Vol.10 No.1

Slipping during various kinds of movement often leads to potentially dangerous incidents of falling. The purpose of this paper was to review some of the research performed in the field including such topics as rating scales for balance, kinematics and kinetics of slipping, adaptation to slippery conditions, postural and balance control, and protective movement during falling. Controlling slipping and fall injuries requires a multifaceted approach. Environmental conditions (state of floor surface, tidiness, lighting, etc), work task (walking, carrying, pushing, lifting, etc), and human behavior (anticipation of hazards, adaptation to risks, risk taking, etc) must be accounted for in the assessment of slip and fall-related risks. Future directions of research must deal with modeling of basic tribophysical, biomechanical, and postural control process involved in slipping and falling.

정상 보행과 발가락 보행의 하지 근육 근 활성도 비교 : An Electromyographic Analysis3.

김택훈,최흥식,김창인,이진복 한국전문물리치료학회 2002 한국전문물리치료학회지 Vol.9 No.2

This study was designed to identify the effects of walking conditions (normal walking vs. toe-walking) on electromyographic (EMG) activity of gastrocnemius, tibialis anterior, and soleus muscle. Seven healthy adult males participated in this study. The exclusion criteria were orthopedic or neurologic disease, congenital anomaly or acquired deformity, or pain in low back or lower extremities. The maximal voluntary isometric contraction for each muscle was used for the reference contraction, and EMG activity of each muscle during normal walking and toe-walking was expressed as a percentage of reference contraction. The gait cycle was determined with two foot switches, and gait was normalized as 100% gait cycle for each condition. The maximal values of EMG activity in terminal stance (30~50% of gait cycle) of each condition were compared for data analysis. No significant differences were found in EMG activity of the tibialis anterior and soleus (p<.05), whereas significant decrement was found in EMG activity of gastrocnemius during toe-walking compared to normal walking (p<.05). There is a limitation to generalize the results of this study, because small number of subjects participated for this study and only EMG was used for data collection. The treatment methods should be developed to improve gait efficiency by substituting the weakened muscles secondary to upper motor neuron, or by strengthening the distal muscles in lower extremity.

노인의 하지 근력강화운동이 기립균형에 미치는 영향

김택훈,오동식 한국전문물리치료학회 2000 한국전문물리치료학회지 Vol.7 No.1

The purpose of this study is to determine the effect of exercise training on the strength and balance ability of the elderly. The results of this study are: 1) After 8 weeks exercise training, knee muscle strength showed a significant increment. 2) After exercise training, forward functional reach and balance index of KAT 2000 showed a significant increment. Results indicate that strengthening exercise can result in improved muscle strength and balance in the elderly. Further studies are required to show long-term effects of exercise training on the elderly.

Parotec System을 이용한 족저압 측정의 신뢰도

노정석,김택훈 한국전문물리치료학회 2001 한국전문물리치료학회지 Vol.8 No.3

In-shoe measurement systems allow the clinician and researcher to examine the pressure parameters within the shoe. The purpose of this study was to investigate the test-retest reliability of plantar pressures using the Parotec system over speeds and plantar regions. Seventeen healthy subjects were recruited for the study. Sampling rate was 100 Hz, and data of six variables (pressure on medial heel, lateral heel, 1st metatarsal head, 5th metatarsal head, and great toe and total impulse) were collected in four different gait speed (1.0 m/sec, 1.5 m/sec, 2.0 m/sec, and comfortable walking speed) in each day. The result indicates fair to excellent reliability between the two day test. Intraclass correlation coefficients (ICCs) ranged from .693 to .979, and range of reliability was similar depending on the speed and plantar region. In most cases, data recorded by the Parotec systems provide good evidence for the reliability.

척수손상인의 기능적 전기자극을 이용한 보행

이재호,김택훈 한국전문물리치료학회 1996 한국전문물리치료학회지 Vol.3 No.3

무지 외반증 환자의 hard insole 착용에 의한 중족지절관절 각도의 변화

임성태,김택훈,최흥식,노정석,김장환 한국전문물리치료학회 2001 한국전문물리치료학회지 Vol.8 No.2

The purpose of this study was to investigate the effect of donning of a hard insole in patients with hallux valgus. Fourteen subjects were selected from patients with foot pain at Lee Chang-Heon Foot Clinic from August 4,2000 to September 15, 2000. The hallux valgus angle and the first-second intermetatarsal angle were radiographically measured before and after donning the hard insole. Based on these two kinds of angles, a mild hallux valgus deformity group was characterized by the hallux valgus angle of less than 20 degrees, and a moderate hallux valgus deformity group was characterized by the hallux valgus angle of 20 to 40 degrees. After three weeks with the hard insole donned, the foot angles of the patients with hallux valgus were measured again. The data were analyzed by Wilcoxon signed ranks test, and the following results were obtained: 1) After the trial, both mild hallux valgus deformity group and moderate hallux valgus deformity group demonstrated that the hallux valgus angles were significantly decreased. 2) After the trial, mild hallux valgus deformity group demonstrated that the first-second intermetatarsal angle was significantly decreased. 3) After the trial, moderate hallux valgus deformity group demonstrated that the first-second intermetatarsal angle was not significantly decreased. The above findings revealed that according to donning hard insole, the hallux valgus angles of mild and moderate hallux valgus deformity groups and the first-second intermetatarsal angle of mild hallux valgus deformity group were significantly decreased. The results of this study have some limitation for generalization due to the limited number of subjects. Further studies are needed to evaluate the effect of hard insole on hallux valgus with more precise laboratory equipments and measurements in patients with hallux valgus.

수행에 대한 지식의 상대적 빈도가 편마비 환자의 균형 재훈련에 미치는 영향

오동식,최흥식,김택훈,노정석 한국전문물리치료학회 2001 한국전문물리치료학회지 Vol.8 No.1

During therapy sessions, feedback is often provided concurrently by the physical therapist as the patient attempts to perform a movement and after the movement attempt. This feedback is provided to enhance the patient's balance abilities. However, recent studies in nondisabled populations have suggested that frequent feedback may be detrimental to retention or learning of motor skills. This study compared the effects of 100% relative frequency of knowledge of performance (KP) with 66% relative frequency of KP for motor learning on balance retraining in patients with hemiplegia. Twenty patients with hemiplegic were randomly assigned to one of two experimental groups. The acquisition phase consisted of 16 blocks of 5 trials for 2 days (80 total practice trials). The retention chase consisted of 2 blocks of a short-term retention test, one day after the end of the acquisition phase and a long-term retention test, one week after the end of the short-term retention test. In the 100% feedback condition, participants received feedback after every practice trial. A faded KP schedule was used in the 66% condition. No significant differences were found between the two groups during all experimental phases (acquisition and retention phases), (p>.05). However, there were significant decreases in balance index for both groups of acquisition phase (p<.05). These results suggest that 66% relative frequency of KP is not more effective than 100% relative frequency of KP with respect to retention over time when hemiparetic patients attempt to learn balance.

운동전략이 기립자세의 기능적 전방 팔뻗기에 미치는 영향

박제상,권오윤,최흥식,김택훈 한국전문물리치료학회 2000 한국전문물리치료학회지 Vol.7 No.1

The purpose of this study is to determine whether movement strategies affect functional forward reach distance in a standing position. Forty-seven healthy subjects were selected for this study: 23 men and 24 women, with an average age of 22.3. Functional forward reach distances were measured as hip strategy and squat strategy(included knee and ankle movement strategy) in a standing position, respectively. The mean values of functional forward reach distance in hip strategy, squat strategy were 33.57㎝, 29.48㎝, respectively. There was significantly difference in functional forward reach distance between hip strategy and squat strategy(p<.001). There was no difference of functional forward reach distance between male and female in hip strategy, but there was significant difference in other strategy(p<.05). These results suggest that movement strategies should be considered during functional forward reach test in standing. Further study is required to determine whether movement strategies affect functional reach distance in elderly and disabled groups.

Tuning the interparticle distances in self-assembled gold nanoparticle films with their plasmonic responses

Kim, In-Hyun,Kim, Ji Hoon,Choi, Jeong-Yong,Shin, Chae Ho,Kim, Jung-Hwan,Bae, Gyun-Tack,Shin, Kuan Soo Elsevier 2019 Chemical physics letters Vol.715 No.-

<P><B>Abstract</B></P> <P>This study presents the fabrication and characterization of imine-functionalized Au nanoparticle (Au NP) film using Poly (ethyleneimine) (PEI) as a reducing and surface stabilizing reagent. The PEI-capped Au NPs can be self-assembled at the water-hexane interface by adding alcohol containing alkanethiol. Furthermore, large-area film made from PEI and alkanethiol-capped Au NPs is produced on a glass substrate with varying interparticle distances that can be controlled by the alkyl chain lengths, ranging from C2 (ethanethiol), C4 (1-butnaethiol), C6 (1-hexanethiol), C8 (1-octanethiol), to C10 (1-decanethiol) at the water-hexane interface. These 2D films show strong collective localized surface plasmon resonance (LSPR) extinction bands that are tunable via near-field coupling of adjacent Au NPs. Pronounced chain-length-dependent red shifts of the SPR bands have been observed for the PEI-capped Au films. The obtained PEI-capped Au films exhibit distinct interparticle-distance-dependent SERS characteristics.</P> <P><B>Highlight</B></P> <P> <UL> <LI> Investigates the localized surface plasmon resonance (LSPR) properties of 2D film of Au nanoparticles on a glass substrate formed at the water-hexane interface. </LI> <LI> 2D films of the Au nanoparticles with the ability to control the interparticle distances by the alkyl chain lengths of alkanethiol. </LI> <LI> Density functional theory (DFT) calculation and finite-difference time domain (FDTD) simulation have been used to confirm the interparticle distances. </LI> <LI> Au nanoparticles and also exhibit distinct interparticle-distance-dependent surface-enhanced Raman scattering (SERS) characteristics. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>