• Title/Summary/Keyword: Bearing mechanism

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The Mechanism for Analgesic Effects of Electroacupuncture on Surgical Ankle Sprain Model Classified as Grade 3 in Rats (수술적 방법으로 유도된 3단계 발목염좌에 대한 전침의 진통기전 연구)

  • Yang, Seung-Bum;Choi, Suck-Jun;Lee, Sung-Ho;Kim, Min-Su;Sohn, In-Chul;Kim, Jae-Hyo
    • Korean Journal of Acupuncture
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    • v.30 no.4
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    • pp.220-229
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    • 2013
  • Objectives : Electroacupuncture(EA) has been used effectively in producing analgesia on ankle sprain pain of humans and animals. Currently to examine the underlying mechanisms of the EA-induced analgesia, the effects of EA on weight-bearing forces(WBR) were examined at ankle sprain classified as grade 3 in rats. Methods : The severe ankle sprain classified as grade 3 was induced surgically by ankle ligament injury in the Sprague-Dawley rats. WBR of the affected foot were examined to evaluate effects and mechanism of EA(2 Hz, 1 ms pulse width, 2 mA intensity, for 15 min) which was applied to either SI6, GB34, or GB39 acupoints. The rats were pretreated with naltrexone(10 mg/kg, i.p.) as an opioid receptor antagonist or phentolamine(5 mg/kg, i.p) as an ${\alpha}$-adrenoceptor antagonist at 30 min before EA. Results : The daily repeat EA at either SI6, GB34, or GB39 showed significant analgesic effects on the severe ankle sprain. Particularly, daily EA at GB34 showed more potent analgesic effect than the others. In addition, the naltrexone pretreatment completely blocked the analgesic effect of EA at GB34, indicating the involvement of the endogenous opioid system in mediating the effect of EA at GB34. However, the phentolamine pretreament blocked analgesic effects of EA at either SI6 or GB39, indicating the involvement of ${\alpha}$-adrenoceptors in mediating the effect of EA at either SI6 or GB39. Conclusions : These data suggest that EA-induced analgesia on ankle sprain pain is mediated through either endogenous opioids or ${\alpha}$-adrenoceptors dependant on acupoint specific pattern.

The Anticancer Effects and Drug Metabolic Enzyme Change by Intraperitoneal Injection of Agrimonia Pilosa Ledeb (선학초 (짚신나물) 복강주사의 항암효과 탐색 및 약물 대사효소의 변화)

  • Choi, Jung-Won;Jang, Bo-Hyung;Lee, Ju-Ah;Ko, Ho-Yeon;Jung, Hee;Jun, Chan-Yong;Park, Jong-Hyung;Kim, Ji-Hye;Ko, Seong-Gyu;Choi, You-Kyung
    • The Journal of Korean Medicine
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    • v.30 no.4
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    • pp.129-141
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    • 2009
  • Objective: This study was to investigate the anti-tumor effect, safety, safety, mechanism and metabolizing enzyme of Agrimonia pilosa LEDEB (APL) in female C57B/L mouse tumor (in vivo). Method: First, to evaluate the antitumor activity of APL, we divided the mice into four groups: normal, control, APL50 (50mg/kg), and APL100 (100mg/kg). LLC-obtained American Type Culture Collection was used. LLC had been inoculated to induce tumors. To measure the anti-tumor effect of APL, we calibrated tumor size and weight. To analyze the mechanism of anti-tumor in APL, we used western blotting and to observe metabolizing enzyme in APL we used to real-time PCR. Result: APL50 and APL100 significantly inhibited tumor growth from 12 days after medicine injected. APL did not induce caspase-dependent apoptosis in LLC-bearing mouse tumor. In APL100, it decreased 41% and 71% in CYP2D22 and CYP3A11, respectively. Conclusion: These results suggest that APL has some anti-tumor effects in female C57B/L mouse tumor. APL should be used carefully with other drugs related with CYP2D22 and CYP3A11.

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KNEE: Basic Science and Injury of Bone (슬관절 주위 글격의 기초과학 및 스포츠 손상)

  • Kim Hee-Chun
    • Journal of Korean Orthopaedic Sports Medicine
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    • v.2 no.2
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    • pp.77-81
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    • 2003
  • Purpose: The biomechanics and kinematics of knee joint were reviewed in this article. And then the common sports injuries were presented. Anatomy and Kinetics: None of the pairs of bearing surfaces in the knee joint is exactly congruent This allows the knee six degrees of freedom of motion. Tibiofemoral Kinematics: In flexion and extension, the axis of motion is not perpendicular to the medial-lateral plane of the joint, nor is it perpendicular to the axis of longitudinal rotation. This results in coupled varus angulation and internal rotation with flexion and in valgus angulation and external rotation with extension. Patellofemoral Articulation: Loads across the patellofemoral joint are indirectly related to the angle of knee flexion and directly related to the force generated within the quadriceps mechanism. Fractures of the Patella: Nonoperative treatment is indicated if the extensor mechanism is intact and if displacement of fragment is minimal. The specific type of internal fixation depends on the fracture pattern. It is important to repair retinaculum. Acute and Recurrent Patellar Instability: The degree of dysplasia and the extent of the instability play a large part in determining the success of nonoperative treatment. Patients who experience recurrent dislocations and patients with major anatomic variations require surgery to minimize their instability. Sports Injuries in School-age Atheletes: Patellar pain in young athletes groups a number of conditions, including Idiopathic Adolescent Anterior Knee Pain, Osgood- Schlatter Disease, and Sinding-Larsen-Johansson Disease.

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A Kinetic Study on Aminolysis of 2-Pyridyl X-Substituted Benzoates: Effect of Changing Leaving Group from 4-Nitrophenolate to 2-Pyridinolate on Reactivity and Mechanism

  • Lee, Jong-Pal;Bae, Ae-Ri;Im, Li-Ra;Um, Ik-Hwan
    • Bulletin of the Korean Chemical Society
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    • v.31 no.12
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    • pp.3588-3592
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    • 2010
  • Second-order rate constants ($k_N$) have been measured spectrophotometrically for nucleophilic substitution reactions of 2-pyridyl X-substituted benzoates 8a-e with a series of alicyclic secondary amines in $H_2O$ at $25.0{\pm}0.1^{\circ}C$. The $k_N$ values for the reactions of 8a-e are slightly smaller than the corresponding reactions of 4-nitrophenyl X-substituted benzoates 1a-e (e.g., $kN^{1a-e}/k_N^{8a-e}$ = 1.1 ~ 3.1), although 2-pyridinolate in 8a-e is ca. 4.5 $pK_a$ units more basic than 4-nitrophenolate in 1a-e. The Br$\o$nsted-type plot for the aminolysis of 8c (X = H) is linear with $\beta_{nuc}$ = 0.77 and $R^2$ = 0.991 (Figure 1), which is typical for reactions reported previously to proceed through a stepwise mechanism with breakdown of a zwitterionic tetrahedral intermediate $T^{\pm}$ being the rate-determining step (RDS), e.g., aminolysis of 4-nitrophenyl benzoate 1c. The Hammett plot for the reactions of 8a-e with piperidine consists of two intersecting straight lines (Figure 2), i.e., $\rho$ = 1.71 for substrates possessing an electron-donating group (EDG) while $\rho$ = 0.86 for those bearing an electron-withdrawing group (EWG). Traditionally, such a nonlinear Hammett plot has been interpreted as a change in RDS upon changing substituent X in the benzoyl moiety. However, it has been proposed that the nonlinear Hammett is not due to a change in RDS since the corresponding Yukawa-Tsuno plot exhibits excellent linear correlation with $\rho$ = 0.85 and r = 0.62 ($R^2$ = 0.995, Figure 3). Stabilization of substrates 8a-e in the ground state has been concluded to be responsible for the nonlinear Hammett plot.

The Anticancer Effects and Drug Metabolic Enzyme Change by Oral Intake of Agrimonia Pilosa Ledeb (선학초(짚신나물) 경구투여시 항암효과 탐색 및 약물 대사효소의 변화)

  • Rhee, Si-Hyung;Jung, Hee;Lee, Ju-Ah;Go, Ho-Yeon;Choi, Yu-Kyung;Park, Jong-Hyung;Kim, Ji-Hye;Ko, Seong-Kyu;Jun, Chan-Yong
    • Journal of Society of Preventive Korean Medicine
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    • v.13 no.2
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    • pp.51-64
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    • 2009
  • Objective : This research was aimed to investigate the anti-tumor effect, safety, mechanism and metabolizing enzyme of Agrimonia pilosa LEDEB(APL) in female C57B/L mouse. Methods : At first, to evaluate the anti-tumor activity of APL, we divided into four groups, normal, control, APL100(100mg/kg), APL150(150mg/kg). LLC obtained American Type Culture Collection was used. LLC had been inoculated to induce tumor. To measure the anti-tumor effect of APL, we calibrate tumor size and weight. To study for mechanism of anti-tumor in APL, we used western blotting and to know metabolizing enzyme in APL we used to real-time PCR. Results : APL100, APL150 inhibited tumor growth after medicine injected. APL did not only induced caspase-dependent apoptosis in LLC-bearing mouse tumor. In APL100, it were decreased 72% in CYP3A11. In APL150, it were decreased 62%, 75% in CYP3A11 and MRP1a respectively. Conclusion : These results suggests that APL has some anti-tumor effects in female C57B/L mouse tumor. APL should be careful use with other drugs related with CYP3A11 or MRP1a.

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A Study on the Comparison of Brazed Joint of Zircaloy-4 with PVD-Be and Zr-Be Amorphous alloys as Filler Metals (PVD-Be와 비정질 Zr-Be 합금을 용가재로 사용한 Zircaloy-4의 브레이징 접합부의 비교 연구)

  • Hwang, Yong-Hwa;Kim, Jae-Yong;Lee, Hyung-Kwon;Koh, Jin-Hyun;Oh, Se-Yong
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.7 no.2
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    • pp.113-119
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    • 2006
  • Brazing is an important manufacturing process in the fabrication of Heavy Water Reactor fuel rods, in which bearing and spacer pads are joined to Zircaloy-4 cladding tubes. The physical vapor deposition(PVD) technique is currently used to deposit metallic Be on the surfaces of pads as a filler metal. Amorphous Zr-Be binary alloys which are manufactured by rapid solidification process are under developing to substitute the conventional PVD-Be coating. In the present study, brazed joint with PVD and amorphous alloys of $Zr_{1-x}Be_{x}(0.3{\le}x{\le}0.5)$ as filler metals are compared by mechanism, microstructure and hardness. The thickness of brazed joint with amorphous alloys became much smaller than that of PVD-Be. The erosion of base metal did not occur in the brazed joint with amorphous alloys. The brazing mechanism for PVD-Be seems to be Be diffusion into Zr-4 with capillary action resulting from eutectic reaction while that for amorphous alloys are associated with the liquid phase formation in the brazed joint. The brazed joint microstructure with PVD-Be consists of dendrite while that with amorphous alloys is globular. The $Zr_{0.7}Be_{0.3}$ alloy shows the smooth interface with little erosion in the base metal and is recommended a most suitable brazing filler metal for Zircaloy-4.

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Study on Antiangiogenic and Antitumor Activities of Processed Rhus verniciflua Stokes extract (법제 옻나무 추출물의 혈관형성저해 및 항암효과에 관한 연구)

  • Choi, Won-Cheol;Lee, Jae-Ho;Lee, Eun-Ok;Lee, Hyo-Jung;Yoon, Sung-Woo;Ahn, Kyoo-Seok;Kim, Sung-Hoon
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.20 no.4
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    • pp.825-829
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    • 2006
  • Rhus verniciflua Stokes has been used for treatment of blood stasis and abdominal mass in Oriental medicine. Rhus verniciflua Stokes has been experimentally reported to exert antioxidant, antiproliferative, antithrombotic and apoptotic activities. In the present study, the antiangiogenic and in vivo antitumor activities of aqueous extract of processed Rhus verniciflua Stokes (Nexia) by heat were examined to elucidate its anticancer mechanism. Nexia showed weak cytotoxiicty against human umbilical vein endothelial cells (HUVEC) and Lewis lung carcinoma cells (LLC) with IC50 of${\sim}200\;{\mu}g/ml\;and\;>200\;{\mu}g/ml$, respectively. Nexia significantly inhibited the proliferation and migratory activity in vascular endothelial growth factor(VEGF) treated HUVEC. Furthermore, Nexia effectively suppressed the tumor volume in A549 nonsmall lung cancer bearing athymic nude mice, CanN. Cg-Foxn 1nu/CrljBgi up to 40.7% as well as tumor weight incised from LLC cells innoculated into the flank of C57BL/6 mice up to -50% compared with untreated control at a dose of 300 mg/kg. Taken together, these results suggest that processed Rhus verniciflua Stokes may inhibit the growth of Lewis lung carcinoma cells partly via inhibition of angiogenesis and can be potently applied to angiogenesis dependent cancers. However, it still needs a further research on molecular mechanism, angiogenesis animal study and clinical trial in future.

A Case Study on Earthquake-induced Deformation of Quay Wall and Backfill in Pohang by 2D-Effective Stress Analysis (2차원 유효응력 해석에 의한 지진시 포항 안벽구조물의 변형 사례 분석)

  • Kim, Seungjong;Hwang, Woong-Ki;Kim, Tae-Hyung;Kang, Gi-Chun
    • Journal of the Korean Geotechnical Society
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    • v.35 no.7
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    • pp.15-27
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    • 2019
  • The purpose of this study is to investigate the mechanism about damages occurring at quay wall and backfill in Youngilman Port during Pohang earthquake (M5.4) on November 15, 2017. In the field investigation, the horizontal displacement of the caisson occurred between 5 cm and 15 cm, and the settlement at backfill occurred higher than 10 cm. 2D-effective Stress Analysis was performed to clarify the mechanism for the damage. The input earthquake motion used acceleration ($3.25m/s^2$) measured at bedrock of Pohang habor. Based on a numerical analysis, it was found that the effective stress decreased due to the increase of excess pore pressure in the backfill ground and the horizontal displacement of the caisson occurred by about 14 cm, and the settlement occurred by about 3 cm. In backfill, the settlements occurred between 6 cm and 9 cm. This is similar to field investigation results. Also, it was found that the backfill soil was close to the Mohr-Coulomb failure line due to the cyclic loading from the effective stress path and the stress-strain behavior. It may be related to decreasing of bearing capacity induced by the reduction of effective stress caused by the increase of the excess pore water pressure.

A Study on the Behaviour of Prebored and Precast Steel Pipe Piles from Full-Scale Field Tests and Class-A and C1 Type Numerical Analyses (현장시험과 Class-A 및 C1 type 수치해석을 통한 강관매입말뚝의 거동에 대한 연구)

  • Kim, Sung-Hee;Jung, Gyoung-Ja;Jeong, Sang-Seom;Jeon, Young-Jin;Kim, Jeong-Sub;Lee, Cheol-Ju
    • Journal of the Korean GEO-environmental Society
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    • v.18 no.7
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    • pp.37-47
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    • 2017
  • In this study, a series of full-scale field tests on prebored and precast steel pipe piles and the corresponding numerical analysis have been conducted in order to study the characteristics of pile load-settlement relations and shear stress transfer at the pile-soil interface. Dynamic pile load tests (EOID and restrike) have been performed on the piles and the estimated design pile loads from EOID and restrike tests were analysed. Class-A type numerical analyses conducted prior to the pile loading tests were 56~105%, 65~121% and 38~142% respectively of those obtained from static load tests. In addition, design loads estimated from the restrike tests indicate increases of 12~60% compared to those estimated in the EOID tests. The EOID tests show large end bearing capacity while the restrike tests demonstrate increased skin friction. When impact energy is insufficient during the restrike tests, the end bearing capacity may be underestimated. It has been found that total pile capacity would be reasonably estimated if skin friction from the restrike tests and end bearing capacity from the EOID are combined. The load-settlement relation measured from the static pile load tests and estimated from the numerical modelling is in general agreement until yielding occurs, after which results from the numerical analyses substantially deviated away from those obtained from the static load tests. The measured pile behaviour from the static load tests shows somewhat similar behaviour of perfectly-elastic plastic materials after yielding with a small increase in the pile load, while the numerical analyses demonstrates a gradual increase in the pile load associated with strain hardening approaching ultimate pile load. It has been discussed that the load-settlement relation mainly depends upon the stiffness of the ground, whilst the shear transfer mechanism depends on shear strength parameters.

A Critical Approach on Environmental Education Biased to Environmental Possibilism - From Clearing up the Cause to Problem-Solving Mechanism - (환경관리주의 환경교육에 대한 비판적 고찰 - 원인규명에서 해결기제로의 전환을 위하여 -)

  • Kim, Tae-Kyung
    • Hwankyungkyoyuk
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    • v.18 no.3 s.28
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    • pp.59-74
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    • 2005
  • We can't deny Korean EE has basically developed on the basis of Environmental Possibilism (Environmental management or Reformism) in lots of aspects. I would show three representative proofs here, the first, the philosophy of Korean EE has been mainly focused on dichotomy of human-techno centrism and eco-centrism with no considering other alternative environmentalism since 4th Formal Curriculum, 1981. The second, simultaneously, the concept of EE has not distinguished from it of Science education. (Furthermore, unfortunately some says EE has been a part of Science education, although there should be many differences on its contextual aspect.) And the third one is that the limit of possibilism which market economists have worried, has scarcely mentioned in various kinds of EE-related teaching materials. Possibilism is basically likely to be accompanied by science and economics-oriented approach, and in this aspect this dichotomy, human-techno centrism and eco-centrism, has come from perspectives of Economical development process and over-addicted belief to Science. So it is enough to say that Korean EE has basically developed with biased to Environmental possibilism, in other words, biased to preference to it. And I'll critically focus on these two axes of possibilism, Science and Economics and its dichotomy. Of course, we should accept there are so many same parts in its contents between EE and Science, but we should know its contextual differences for triangular position of environmentalism suitable to EE and also overcome science-dependant approach to EE. Although science-dependant approach to EE and dichotomy could provide some tools for clearing up the causes of environmental problem, especially always it has insisted fundamental causes of environmental problem originated in human faults and over-use of eco-source or over-economic development, but now it is old-fashioned discourse, furthermore it come to have unavoidable limits in the debates of problem-solving mechanism to environmental problems. The paramount important thing is to supply the ways or thoughtful mechanism for solving or coordinating the Environmental problems, not just searching for cause of it. But scientific approach and its dichotomy based on possibilism have continuously born cause & effect in EE-related discourse. So there are so much needs to transfer from continuous bearing of cause & effect to constructive alternatives at least in environmentalism of EE. Traditionally, dichotomical division in EE Environmentalism, human-techno centrism and eco-centrism, couldn't have Provided any answers to our real society, it just gives us only cause & effects of Environmental problems. And also we can't find the description on the limits of capitalism market approach to Environmental problems especially in Korean EE text books, other teaching materials and its teaching-learning process, although market approach economist has been proved its fault beyond its functional merits as Environmental management tools. So we should introduce other alternative Environmental philosophy instead of Possibilism such as eco-socialism insisted by Schmacher M. and Boochin etc, or marxist-environmentalism for relative and comparative views to market-thought such as commodification. In this aspect we need to accept Oriental philosophy based on moderation(中庸) as new another alternatives with the reflection that we have recognized monism as representative Oriental philosophical environmentalism. Fundamentally monism has done its role with providing relative concepts to Dichotomy Enlightenment, but we can't say it has been core concept for understanding of oriental environmentalism, and we can't distinguish monism from oriental philosophy itself, just because oriental thought itself was basically monism. So conceptual difference should be recognized between EE and Science education in teaching-learning process on the basis of life-philosophy(Philosophie des Lebens) from epistemology. For this transformation, we should introduce existentialism in Science education, in other words, only existential Science education based on phenomenology or interpretivism can be EE. And simultaneously we need some ways for overcoming of scientific foundationalism which has been tradition making science not stand on existentialism, formulating and featuring of almost all of natural things and its phenomenon from after enlightenment in western world, but it has malfunctioned in fixing conception of science just into essentialism itself. And we also introduce integrated approach to science and society for EE like STS. Those are ways for overcoming of Environmental possibilism in EE.

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