• Title/Summary/Keyword: surface activation

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Influences of Short-term High-heeled Walking on the Activities of Ankle-stabilizing Muscles in Healthy Young Females (단시간 하이힐 보행이 젊은 여성의 발목 주위근의 근 활성도에 미치는 영향)

  • Kim, Eun-ji;Jeon, Seol-bin;Jeong, Ki-yong
    • The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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    • v.21 no.2
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    • pp.39-46
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    • 2015
  • Background: The purpose of this study was to investigate the influence of short-term treadmill walking with high-heeled shoes on electromyography activities of the medial gastrocnemius, lateral gastrocnemius and tibialis anterior in healthy young females. Methods: Fifteen healthy females were recruited for this study. To measure muscle activation, the subjects were asked in random order to walk on a treadmill using either high-heeled shoes or barefoot conditions. The shoe heel height for high-heeled walking was 7 cm. The walking speed on the treadmill was 4 km/h, and the inclination rate of the treadmill was 10%. The subjects performed treadmill walking in the barefoot and high-heeled walking conditions for 5 minutes. Electromyography data were collected from the tibialis anterior, medial gastrocnemius, lateral gastrocnemius, and soleus on both firm and foam surfaces and during eyes-open and-closed conditions while standing. Results: Tibialis anterior activity was significantly different before and after the walking task while standing on a foam surface with eyes closed (p<.05). Conclusion: This finding suggests that the activity of the tibialis anterior may be lowered after high-heeled walking. Therefore, high-heeled shoes contribute to harmful effects at the ankle joints, increasing the risks of falling and musculoskeletal injury.

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The Effect of Cu Loading on the Performance of Cu-Ce0.8Zr0.2O2 Catalysts for Single Stage Water Gas Shift Reaction (컴팩트 개질기용 수성가스전이 반응에서 Cu-Ce0.8Zr0.2O2 촉매에 Cu 담지량이 미치는 영향)

  • KIM, HAK-MIN;JEON, KYUNG-WON;NA, HYUN-SUK;JANG, WON-JUN;JEONG, DAE-WOON
    • Transactions of the Korean hydrogen and new energy society
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    • v.28 no.4
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    • pp.345-351
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    • 2017
  • Single stage water-gas shift reaction has been carried out at a gas hourly space velocity of $150,494h^{-1}$ over $Cu-Ce_{0.8}Zr_{0.2}O_2$ catalysts prepared by a co-precipitation method. Cu loading was optimized to obtain highly active co-precipitated $Cu-Ce_{0.8}Zr_{0.2}O_2$ catalysts for single stage water-gas shift reaction. 80 wt.% $Cu-Ce_{0.8}Zr_{0.2}O_2$ exhibited the excellent catalytic performance as well as 100% $CO_2$ selectivity (CO conversion = 27% at $240^{\circ}C$ for 50 h). The high activity and stability of 80 wt.% $Cu-Ce_{0.8}Zr_{0.2}O_2$ are correlated to low activation energy and large amount of surface Cu atoms.

Kinetics of 125I-BSA Binding to Monoclonal Anti-BSA Immobilized on $0.5{\mu}m$ Polystyrene Beads (c크기의 폴리스타이렌 담체에 고정화된 단세포군 항체와 항원 BSA의 속도론)

  • ;Dan
    • KSBB Journal
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    • v.11 no.2
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    • pp.225-237
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    • 1996
  • Intrinsic binding kinetics of of 125I-bovine serum albumin (125I-BSA) and immobilized monoclonal anti-BSA (MAb 9.1) were studied. Small non-porous polystyrene beads (0.5${\mu}$m diameter) were used as a solid support to minimize the mass transfer interference on rate measurements. We demonstrated both theoretically and experimentally that the binding reaction is kinetically controlled. Rate measurements show that the association reaction is of second order and the dissociation reaction is of first order. Between 4 and $37^{\circ}C$ the measured equilibrium constant agrees well with the equilibrium constant calculated from the rate measurements. The temperature effects on association are much greater than on dissociation; the activation energy for association is about 9Kca1/mole, as compared to 2Kca1/mole for dissociation. The use of small non-porous beads as a solid support in binding studies essentially avoids mass transfer limitations; such a system makes it possible to determine the intrinsic binding characteristics of any immobilized antibody on a solid surface.

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Kinetics of Catalytic Oxidation of Vinyl Chloride over CrOx/γ-alumina (CrOx/γ-alumina 촉매상에서 Vinyl Chloride의 산화반응 속도해석)

  • Lee, Hae-Wan;Kim, Young Chai;Moon, Sei-Ki
    • Applied Chemistry for Engineering
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    • v.10 no.1
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    • pp.85-92
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    • 1999
  • The complete catalytic oxidation of vinyl chloride was investigated over chromium oxide supported ${\gamma}$-alumina using a fixed bed micro-reactor at temperature between 240 and $300^{\circ}C$ and concentration between 600 and 3500 ppm. The oxidation of vinyl chloride was nonlinear in the concentration of vinyl chloride and zeroth order in the concentration of oxygen. The addition of HCl and $H_2O$ as products to the feed stream didn't influence the conversion of vinyl chloride. Several kinetic rate model were tested to describe the data over the range of condition investigated, and developed a model which provide the best correlation of experimental data. The resulting model of kinetic rate was derived by assuming that the reacting occurred via adsorption and subsequent decomposition of the vinyl chloride onto the oxygen covered chromium oxide surface, with the reaction being inhibited by the adsorption of vinyl chloride. The percent standard deviation between the predicted and experimental was about 5.2%, and the activation energy was 18.9 kcal/mol.

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The Effects of 120 Hz High Frequency Electroacupuncture on the Gastric Mucosa in Cold-Restraint Stressed Rats (고빈도 120 Hz 전침이 Cold-Restraint 스트레스 유발 흰쥐의 위점막에 미치는 영향(影響))

  • Jo, Mee-Hyeong;Ahn, Chang-Beohm;Song, Choon-Ho;Yoon, Hyoun-Min;Kim, Cheol-Hong;Jang, Kyung-Jeon
    • Korean Journal of Acupuncture
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    • v.21 no.4
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    • pp.101-115
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    • 2004
  • Objective : The present studies investigated the effects of 120 Hz high frequency electroacupuncture (EA) on the stress-induced stomach dysfunction in relation to its effect on the level of stress hormones and gastric mucosal damages. The gastric mucosal injury was induced by cold-restraint stress and two acupoints corresponding to Zusanli and Sanyinjiao in man were used. Methods : Cold-restraint stress produced typical gastric lesions in all rats of the stressed groups, but the number of ulcers as well as the mean ulcer diameter were reduced by 120 Hz EA pre-treatment. Results : The degranulation value of gastric mast cell was significantly higher in cold-restrained rats than in control ones. However, with the significant reduction of degranulation values of gastric mast cells in EA pre-treated rats compared with cold-restrained rats. Cold-restarint stress induced an elevated mRNA expression of pro-inflammatory gene such as cyclooxygenases-2 and tumor necrosis factor $(TNF)-{\alpha}$, but these expression were down-regulated in EA pre-treated rats. Immunohistochemical analysis showed that while the $inhibitory-{\kappa}B{\alpha}$ and $TNF-{\alpha}$ immunorection in the surface epithelium of the stomach tended to increase, both reactions in the EA pre-treated rats showed similar pattern as observed in controls. Conclusion : These results suggest that 120 Hz EA may act as a therapeutical means for gastric mucosal damages through an activation of pituitary adrenal system. It could be concluded that 120 Hz high frequency electroaucupuncture affords a good protective potential against stress-induced gastrointestinal dysfunction.

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Modification of Substrate Inhibition of Synaptosomal Acetylcholinesterase by Cardiotoxins

  • Ranaei-Siadat, Seyed-Omid;Riazi, Gholam-Hosein;Sadeghi, Mehdi;Chang, Long-Sen;Lin, Shinne-Ren;Eghtesadi-Araghi, Peyman;Hakimelahi, Gholam Hossein;Moosavi-Movahedi, Ali Akbar
    • BMB Reports
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    • v.37 no.3
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    • pp.330-338
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    • 2004
  • Different types of cardiotoxin (I-V and n) were isolated and purified from the venom of the Taiwan cobra (Naja naja atra). The effects of these cardiotoxins were studied on membrane-bound acetylcholinesterase, which was isolated from a sheep's brain cortex. The results showed that cardiotoxins I-III, V, and n activated the enzyme by modification of substrate inhibition, but cardiotoxin IV's reaction was different. The inhibition and activation of acetylcholinesterase were linked to the functions of the hydrophobicity index, presence of a cationic cluster, and the accessible arginine residue. Our results indicate that Cardiotoxins have neither a cationic cluster nor an arginine residue in their surface area of loop I; therefore, in contrast to fasciculin, cardiotoxins are attached by loop II to the peripheral site of the enzyme. As a result, fasciculin seems to stabilize nonfunctional conformation, but cardiotoxins seem to stabilize the functional conformation of the enzyme. Based on our experimental and theoretical findings, similar secondary and tertiary structures of cardiotoxins and fasciculin seem to have an opposite function once they interact with acetylcholinesterase.

The Comparison of Electromyographic Ratio of Serratus Anterior and Upper Trapezius According to Exercise Position and Shoulder Flexion Angle during Scapular Protraction Exercises (어깨뼈 내밈 운동 시 운동 자세와 어깨관절 굽힘각도에 따른 앞 톱니근과 위 등세모근의 근 활성도 비의 비교)

  • Koh, Eun-Kyung;Weon, Jong-Hyuck;Jung, Do-Young
    • Korean Journal of Applied Biomechanics
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    • v.22 no.2
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    • pp.193-199
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    • 2012
  • The purpose of this study was to investigate the activities of the serratus anterior (SA) and upper trapezius (UT) muscles during scapular protraction exercise with a dumbbell. Twenty-one healthy subjects with no medial history of shoulder pain or upper extremity disorders were recruited for this study. Subjects performed scapular protraction at $90^{\circ}$ and $130^{\circ}$ shoulder flexion with a dumbbell in supine and standing positions. The activities of the SA and UT were measured via surface electromyography (EMG) during 4 scapular protraction exercises. A 2 (angle) ${\times}$ 2 (position) repeated-measures analysis of variance (ANOVA) was used to compare the normalized activities of the SA and UT and the UT/SA ratio. The results showed that activities of both the SA and UT were the highest for the scapular protraction exercise at $130^{\circ}$ shoulder flexion in the standing position. However, the UT/SA ratio was the lowest for the exercise at $90^{\circ}$ shoulder flexion in supine position. Therefore, for selective activation of the SA muscle, we recommend performing the scapular protraction exercise with a dumbbell in the supine position at $90^{\circ}$ shoulder flexion.

Hemagglutinative Activity of Lectin Isolated from Shiitake, Lentinula edodes (표고버섯에서 분리한 렉틴의 적혈구 응집활성)

  • Kim, Young-Shin;Lim, Chi-Hwan;Cho, Nam-Seok
    • The Korean Journal of Mycology
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    • v.30 no.1
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    • pp.31-36
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    • 2002
  • Since lectin condense more easily cancer cell than normal cell, it has been investigated very actively. Recently, a lot of researchers gave attention to lectin in natural products especially because lectin has effects on T-cell activation and anticancer activity, and specificity on polysaccharide. The specificity is useful to confirm kind of polysaccharide of the cell surface and to study the polysaccharide. In this research, we purified lectin from shiitake, Lentinula edodes, and then characterized it. The molecular weight of the lectin was 23 kDa, and it was stable only under the $40^{\circ}C$ and in a alkaline solution. As for the specificity of polysaccharide, the lectin had specificity on galactose, fucose, glucose, lactose and N-acetyl-D-galactosamine. In addition, it was confirmed to be a glycoprotein.

Effect of Visual and Palpation Feedback on Muscle Activity of Gluteus Maximus and Motion of Pelvic Rotation during Clam Exercise (크램 운동 시 시각-촉진 되먹임이 큰볼기근 활성도와 골반 회전에 미치는 영향)

  • Koh, Eun-Kyung;Jung, Do-Young
    • The Journal of Korean Physical Therapy
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    • v.25 no.5
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    • pp.337-342
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    • 2013
  • Purpose: This study was conducted in order to determine the effect of visual and tactile feedback on muscle activity of the gluteus maximus (Gmax) and abdominal muscles and the motion of pelvic rotation during performance of clam exercise (CE). Methods: Thirteen subjects without low back pain were recruited for this study. Each subject was instructed to perform the CE without and with feedback. The subjects were instructed to keep pelvic from rotating backwards by palpating the ASIS and monitoring the pelvic movement by themselves during performance of CE with feedback. The electromyographic (EMG) activities of Gmax and abdominal muscles were collected using surface EMG. Angles of pelvic rotation were measured using a 3-dimensional motion-analysis system. Paired t-tests were used for comparison of EMG activities in each muscle and the angle of pelvic rotation. Results: The EMG activities of all abdominal muscles were not significant between CM without and CM with feedback (p>0.05). The EMG activity of Gmax was significantly greater in CM with feedback compared with CM without feedback (without vs. with feedback; 14.2% vs. 20.7%MVIC) (p<0.05). The angle of pelvic rotation was significantly less in CM with feedback compared with CM without feedback (without vs. with feedback; $15.3^{\circ}$ vs. $10.8^{\circ}$ ) (p<0.05). Conclusion: Therefore, these findings suggest that CM with the visual and tactile feedback is effective in activation of the Gmax and correcting of the uncontrolled lumbopelvic rotation during CE.

Effect of Shoulder Position on Scapular Muscle Activity during Scapular Protraction

  • Yun, Sung Joon;Kim, Moon-Hwan;Weon, Jong-Hyuck
    • The Journal of Korean Physical Therapy
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    • v.32 no.3
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    • pp.157-162
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    • 2020
  • Purpose: This study was to evaluate several tasks performed at a high intensity in terms of their ability to elicit EMG activity in the serratus anterior by comparing the EMG activities of the serratus anterior, upper trapezius, and lower trapezius muscles during six tasks combined shoulder flexion with rotation. Methods: Fifteen healthy males were recruited to this study. Each subject was instructed to assume a sitting position without back support and asked to flex (90° or 120°) the right shoulder and protract the scapula in the sagittal plane with maximal external rotation; to assume a neutral position; or to internally rotate the glenohumeral joint. The EMG data were collected from the serratus anterior (SA), upper trapezius (UT), and lower trapezius (LT) muscles were normalized to maximum voluntary isometric contraction. The UT/LT and UT/SA muscle activity ratios in each task were assessed by calculating the surface EMG. Data were analyzed by two-way repeated-measures analysis of variance, with the level of significance set at p<0.05. Results: The results of this study, shoulder flexion with external rotation resulted in low upper trapezius/serratus anterior and upper trapezius/lower trapezius ratios and a relatively high level of serratus anterior activation. Conclusion: Shoulder flexion with external rotation used herein may be considered as important for clinical interventions aimed at selectively increasing SA strengthen and clinical selection of exercises for improving glenohumeral joint and scapulothoracic control.