• Title/Summary/Keyword: PU

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A Systematic Review of the Effectiveness of Eastern-Western Integrative Medicine for Musculoskeletal Disorders (근골격계 질환의 한·양방협진치료 효과 연구에 대한 체계적 문헌 고찰)

  • Lee, Seung-Jin;Shin, Byung-Cheul;Song, Geun-Sung;Hwang, Eui-Hyoung;Yun, Young-Ju;Cho, Hyun-Woo
    • Journal of Korean Medicine Rehabilitation
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    • v.21 no.4
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    • pp.87-96
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    • 2011
  • Objectives: This study aims to systematically evaluate the effectiveness of Eastern-Western integrative medicine for musculoskeletal disorders compared with Eastern or Western Medicine. Methods: Systematic sea-mes of 9 major Korean databases were conducted for articles published up to July 2011. Searching keyword was "Integrative Medicine". Prospective studies dealt with musculoskeletal disorders by Eastern-Western integrative medicine were included. Quality assessment of included studies was evaluated by Cochrane risk of bias tool. Results: 470 studies in total were seamed, Amalg them 7 studies met our inclusion criteria(3 randomized controlled clinical trials, 2 non-randomized controlled trials and 2 uncontrolled clinical trials). Included studies dealt with lumbar pan(3), shoulder pain(2), pain after traffic injury(1), spinal compression fracture(1). Eastern-Western integrative medicine showed better or equal effect for the treatment of various muscloskeletal disorders compared with Eastern or Western medicine alone. Conclusions: There is very weak evidence for the effectiveness of Eastern-Western integrative medicine for musculoskeletal disorders compared with Eastern or Western medicine alone. Well designed randomized controlled trials with rigorous methodology are needed to evaluate the effectiveness of Eastern-Western integrative medicine objectively in the future.

The Effect of Fluid Shear Stress on Endothelial Cell Adhesiveness to Modified Polyurethane Surfaces

  • Gilson Khang;Lee, Sang-Jin;Lee, Young-Moo;Lee, Jin-Ho;Lee, Hai-Bang q
    • Macromolecular Research
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    • v.8 no.4
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    • pp.179-185
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    • 2000
  • Generally vascular grafts with a relatively large inner diameter (> 5 mm) have been successfully employed for replacement in the human body. However, the use of small diameter grafts is limited, because these grafts rapidly occlude due to the thrombosis. The ideal blood-contacting surface of a prosthesis would be an endothelial cell (EC) lining, because the confluent monolayer of healthy ECs that culture natural blood vessels represents the ideal nonthrombogenic surface. For vascular graft application, the stable EC adhesion on surface under How conditions is very important. In this study, the adhesive strength of ECs attached on polymer surfaces coated with collagen type IV (Col IV), fibronectin (Fn), laminin (Ln), and treated with corona was investigated onto polyurethane (PU) films. The EC-attached PU surfaces were mounted on parallel-plate flow chambers in a How system prepared for cell adhesiveness test. Three different shear stresses (100, 150, and 200 dyne/㎠) were applied to the How chambers and each shear stress was maintained for 120 min to investigate the effect of shear stress and surface treatment condition on the EC adhesion strength. It was observed that the EC adhesion strength on the surface-modified PU films was in the order of Ln≡Fn > Col IV > corona 》 control. More than 70% of the adhered cells were remained on surface-modified PU surface after applying the shear stress,200 dyne/㎠ for 2 hrs, whereas the cells were completely detached on the control PU surface within 10 min after applying the same shear stress. It seems that the type of adsorbed proteins and hydrophilicitv onto the PU surfaces play very important roles for cell adhesion strength.

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A novel method with photochemical reaction for LK immobilization on the polyurethane surface (폴리우레탄 표면의 광화학적 공유결합을 이용한 새로운 LK 고정화 방법에 관한 연구)

  • Kim, H.J.;Nakayama, Yasuhide;Shim, J.H.;Ryu, G.H.;Kim, J.;Matsuda, Takehisa;Min, B.G.
    • Proceedings of the KOSOMBE Conference
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    • v.1996 no.05
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    • pp.91-96
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    • 1996
  • 광반응을 이용하여 fibrinolytic 활성을 보이는 LK (lumbrokinase)를 생체재료인 PU (polyurethane) 표면에 고정화하는 방법에 관하여 연구하였다. 먼저 PU표면에 amino 작용기를 도입하기 위하여 side chain 작용기로 phenylazide 와 amino작용기를 갖는 AzPhPAL을 이용하였으며 광반응은 266nm 이상의 UV light을 약 1분간 조사시키는 방법을 이용하였다. LK를 amino작용기가 유도된 PU 표면에 공유결합시키기 위하여 amide결합 형성시 사용되는 수용성 carbodiimide인 EDC를 이용하였다. ESCA측정시, AzPhPAL으로 공유결합시킨 경우 반응하지 않은 PU표면에 비하여 N/C가 0.1717로, LK 고정시 S/C가 0.0043로 증가된것을 알 수 있었다. 이것으로부터 AzPhPAL과 LK가 PU표면에 공유결합된 것을 확인할 수 있었으며 static contact angle 측정으로 표면개질된 PU표면이 소수성에서 친수성으로 변화된 것을 확인 할 수 있었다. 또한 공유결합된 LK의 활성을 확인하기 위하여 fibrin plate test를 실시하였는데 그 결과 고정화된 후에도 LK의 활성이 존재함을 알 수 있었다.

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Effect of Pu'er tea extract on C2C12 myoblast differentiation (보이차 열수 추출물의 근아세포 근분화에 미치는 영향)

  • Lee, Hyoseong;Choi, Sunkyung;Lee, Boyeong;Kim, Eunmi;Lee, Woonghee;Han, Hyosang;Kim, Keekwang
    • Journal of Digital Convergence
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    • v.18 no.12
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    • pp.585-594
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    • 2020
  • At present, aging-related degenerative muscle diseases are considered a serious problem. However, the drug effect on the treatment and prevention of sarcopenia has not been investigated. The purpose of this study was to evaluate the value of extract of Pu'er tea as a remedy to alleviate the symptoms of sarcopenia. Pu'er tea extracts showed excellent radical scavenging ability. The expression of Myh3 was promoted and myotube formation also was increased by treatment of Pu'er tea extracts. These results suggest that Pu'er tea is a natural substance that promotes myogenesis, and is valuable as a material for pharmaceutical research on the prevention and treatment of various muscle diseases, including sarcopenia. And It is necessary to confirm specific indicator substances of puer tea and further study on this.

A Study on Pretreatment and Dyeing Characteristics of High-density Two-way Elastic Knitted Fabric using CDP Yarn and PU Yarn (CDP사와 PU사를 사용한 고밀도 양방향 신축성 편물의 전처리 및 염색 특성에 관한 연구)

  • Cho, Hang Sung;Woo, Jang Chang;Lee, Beom Soo
    • Textile Coloration and Finishing
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    • v.34 no.4
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    • pp.224-233
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    • 2022
  • Recently, consumer tastes of various classes at home and abroad prefer comfortable, unadorned, and simple clothing, and the athleisure trend, which can be used freely in daily life as well as exercise, has expanded to overall clothing products. Existing materials used for athleisure are composite knitted fabrics using polyester yarn and PU yarn, which has problems due to a chronic lack of color fastness and contamination by dyes even when PU laminating is applied, making it difficult to apply various colors. There is a quality problem in which deformation of the product occurs due to lack of durability. In this study, CDP yarn(75de/72f) and PU yarn(40de) were selected to commercialize the circular knitting for athleisure using CDP yarn in order to solve the problems that occur in the dyeing and laminating process when using polyester materials. CDP yarns were used to knit into single(CP75-S) and double(CP75-D) knit and single knit were found to be suitable as athleisure fabrics. After pretreatment and treatment under various conditions, the stainability of CDP circular knitting was examined. After pretreatment and dyeing process under various conditions, the property of scouring and dyeability of CP75-S were evaluated.

Conceptual design study on Plutonium-238 production in a multi-purpose high flux reactor

  • Jian Li;Jing Zhao;Zhihong Liu;Ding She;Heng Xie;Lei Shi
    • Nuclear Engineering and Technology
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    • v.56 no.1
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    • pp.147-159
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    • 2024
  • Plutonium-238 has always been considered as the one of the promising radioisotopes for space nuclear power supply, which has long half-life, low radiation protection level, high power density, and stable fuel form at high temperatures. The industrial-scale production of 238Pu mainly depends on irradiating solid 237NpO2 target in high flux reactors, however the production process faces problems such as large fission loss and high requirements for product quality control. In this paper, a conceptual design study of producing 238Pu in a multi-purpose high flux reactor was evaluated and analyzed, which includes a sensitivity analysis on 238Pu production and a further study on the irradiation scheme. It demonstrated that the target structure and its location in the reactor, as well as the operation scheme has an impact on 238Pu amount and product quality. Furthermore, the production efficiency could be improved by optimizing target material concentration, target locations in the core and reflector. This work provides technical support for irradiation production of 238Pu in high flux reactors.

Geochemical Modeling on Behaviors of Radionuclides (U, Pu, Pd) in Deep Groundwater Environments of South Korea (한국 심부 지하수 환경에서의 방사성 핵종(우라늄, 플루토늄, 팔라듐)의 지화학적 거동 모델링)

  • Jaehoon Choi;SunJu Park;Hyunsoo Seo;Hyun Tai Ahn;Jeong-Hwan Lee;Junghoon Park;Seong-Taek Yun
    • Economic and Environmental Geology
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    • v.56 no.6
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    • pp.847-870
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    • 2023
  • The safe disposal of high-level radioactive waste requires accurate predictions of the long-term geochemical behavior of radionuclides. To achieve this, the present study was conducted to model geochemical behaviors of uranium (U), plutonium (Pu), and palladium (Pd) under different hydrogeochemical conditions that represent deep groundwater in Korea. Geochemical modeling was performed for five types of South Korean deep groundwater environment: high-TDS saline groundwater (G1), low-pH CO2-rich groundwater (G2), high-pH alkaline groundwater (G3), sulfate-rich groundwater (G4), and dilute (fresh) groundwater (G5). Under the pH and Eh (redox potential) ranges of 3 to 12 and ±0.2 V, respectively, the solubility and speciation of U, Pu, and Pd in deep groundwater were predicted. The result reveals that U(IV) exhibits high solubility within the neutral to alkaline pH range, even in reducing environment with Eh down to -0.2 V. Such high solubility of U is primarily attributed to the formation of Ca-U-CO3 complexes, which is important in both G2 located along fault zones and G3 occurring in granitic bedrocks. On the other hand, the solubility of Pu is found to be highly dependent on pH, with the lowest solubility in neutral to alkaline conditions. The predominant species are Pu(IV) and Pu(III) and their removal is predicted to occur by sorption. Considering the migration by colloids, however, the role of colloid formation and migration are expected to promote the Pu mobility, especially in deep groundwater of G3 and G5 which have low ionic strengths. Palladium (Pd) exhibits the low solubility due to the precipitation as sulfides in reducing conditions. In oxidizing condition, anionic complexes such as Pd(OH)3-, PdCl3(OH)2-, PdCl42-, and Pd(CO3)22- would be removed by sorption onto metal (hydro)oxides. This study will improve the understanding of the fate and transport of radionuclides in deep groundwater conditions of South Korea and therefore contributes to develop strategies for safe high-level radioactive waste disposal.

Development of a Core management Algorithm for Optimal Design of AMBIDEXTER Transient Cores (AMBIDEXTER 천이노심 설계최적화를 위한 노심관리 알고리즘 개발)

  • Yu, Geuk-Jong;Sin, Dong-Hun;So, Sun-Gyu;Lee, Yeong-Jun;Kim, Jin-Seong;O, Se-Gi
    • Proceedings of the Korean Nuclear Society Conference
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    • 2004.10a
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    • pp.99-100
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    • 2004
  • AMBIDEXTER-NEC의 천이노심은 $^{Nat}Th$$^{Nat}U$의 주입만으로 전 출력의 Break-even 노심에 도달하기위한 중간 단계이다. 선행연구에서 수행한 전 출력노심인 평형노심의 핵종수밀도에 도달하기 위해서 평형노심에서의 기저물질, 잠재핵분열성물질, 핵분열물질의 수밀도를 각 SEU-기반, Pu-기반, ADS-기반에서 그대로 유지하여 초기노심을 구성하였다. 또 각 시나리오에 대해 최대첨두출력과 원자로의 안전성을 고려해 Excess Reactivity를 5mk 내에서 초기노심을 결정하였다. 각 노심은 주 핵분열성물질 $^{235}U$, $^{239}Pu$$^{233}U$의 핵반응단면적 특성에 따라 평균 전환율이 각각 0.95, 0.83 및 1 .21 로서 핵연료물질의 적절한 선택만으로도 전환로, 연소로 및 증식로로 설계할 수 있음을 보여준다. 이러한 $Th/^{233}U$, U/Pu 핵연료주기를 사용하는 AMBIDEXTER-NEC 용융염핵연료 원자로의 초기노심에서 시작한 천이노심은 평형노심에장전할 충분한 $^{233}U$ 양을 확보해야 하므로 천이노심의 목표는 평형노심 $^{233}U$의 요구량에 최소한의 기간에 가장 적은 외부주입을 통해 도달하는 것이다. 천이노심에서 임계가 유지되는 AMBIDEXTER-NEC 원자로시스템의 3군 핵종변환 코드인 HELIOS-SQUID-AMBIBURN 체제를 개발하였고 그림 1.에 나타내었다. 이 알고리즘은 각 초기노심 중원소의 미시단면적, 중원소를 제외한 원소들의 거시단면적, 임계도를 만족하는 중성자속 및 외부주입율을 계산하여 SQUID 및 AMBIBURN 입력자료를 제공한다. 또한 일정시간 중원소의 핵종농도, 외부주입율과 중성자속이 일정하다는 가정 하 에 반복수행 하고 SEU-기반과 Pu-기반의 경우에는 각각 핵변환을 거쳐 재순환되는 $^{233}U$$^{239}Pu$의 양을 바로 주입하는 최대재순환 경우와 평형노심 요구 장전량에 이를 때까지 시설 내 저장하는 최소재순환 경우로 상황을 모사하였다. 그림 2 는 각 시나리오별 초기노심에서부터 200FPD까지 단위 용융염 체적당 $^{233}U$의 수밀도 시간변화를 나타낸 것이다. 그림을 보면 50일 이후부터는 수밀도의 변화가 일정한 기울기를 보이고 있고 재처리공정에서 $^{233}Pa$를 분리하는 최소재순환의 경우에는 최대재순환보다 2-3%정도에 지나지않아 그림에서 나타내지않았다. SEU-기반 및 Pu-기반에서 $^{233}U$의 증가율이 각각 2.54E+13, 2.81E+13 #/cc/d 로 Pu 기반이 조금 더 큰 증가율을 나타내고 있지만 평형노심 농도 1.04E+20 #/cc/d 에 도달하기 위해서는 두 경우 모두 매우 긴 시간이 걸릴 것을 예상할 수 있다. 요컨대 250MWth AMBIDEXTER-NEC가 평형노심을 이루기 위해 필요로 하는 $^{233}U$을 생산하는데 제안한 SEU-기반, Pu-기반 시나리오는 천이노심주기기간이 전형적인 원자로 수명 3-40년 보다 매우 큰 것으로 나타났다. 따라서 장전될 $^{233}U$의 확보를 위한 최적옵션은 초기노심부터 ADS와 같은 외부생산시설로부터 전량을 공급 받아 운전하는 것이라 판단된다.

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Blood Compatibility of Polyurethane-poly(vinyl alcohol) Polymer Blends (폴리우레탄-폴리비닐알콜 블렌드의 혈액적합성)

  • 김승수;유영미;신재섭;정규식
    • Polymer(Korea)
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    • v.24 no.1
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    • pp.82-89
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    • 2000
  • The blood compatibilities of PU/PVA polymer blends with different mixing ratios were evaluated using various methods, such as fibrinogen adsorption, plasma recalcification time, platelet adhesion, whole blood clotting time, and complement activation. In addition, PVA on the surface of the polymer blends was crosslinked by glutaraldehyde to restrain the mobility of PVA molecules for characterizing the effect of PVA in the polymer blends on blood compatibility. The fibrinogen adsorption on the polymer blends decreased with the increase of PVA amount in the polymer blends. The plasma recalcification times of the polymer blends with 10-50 wt% PVA were longer than those of PU, PVA, and polymer blends with higher amount of PVA. The morphological changes and adhesion of platelets on the polymer blends with 30-50 wt% PVA were less than those on the other materials. The blood clotting times and complement activation on the polymer blends with 30-50 wt% PVA were reduced, compared to the other materials. On the other hand, the blood compatibility of the crosslinked polymer blends was relatively decreased, compared to the non-crosslinked ones. According to these experimental results, the blood compatibility of the polymer blends with 30-50 wt% PVA was better than that of the other materials and such a blood compatibility of the polymer blends might be related to the mobility of PVA molecules on the surface.

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Development of self-sealing waterproof materials using GRT powder (폐타이어 분말을 이용한 자체보수성 방수재 개발)

  • Lee Dong-Min;Choi Joong-So
    • Resources Recycling
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    • v.14 no.4 s.66
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    • pp.22-33
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    • 2005
  • Four sheet-shaped and one soft-shaped self-sealing waterproof materials were prepared to recycle some GRT(Ground Rubber Tires). Their physical properties were tested to consider characteristics of them. The self-sealing waterproof materials were consisted of GRT/super absorbent polymer(SAP)/binder and mold by a hot press after mixing with a batch-typed internal mixer. The average size of GRT particles was -40 mesh, SAPs were commercial GE-500F and poly(AM-SAS-AA) prepared in this work. Binders were PU. EVA, LDPE, SBR, and poly(2-EHA). And PU film was attached to improve the properties of waterproof materials. Characteristics of self-sealing waterproof materials consisted of by GRT/GE-500F/EV-600/PU film and GRT/GE-500F/SBR(vulcanization)/PU film among the developed self-sealing waterproof materials were similar to the commercial products. And properties of the soft-shaped self-sealing waterproof materials consisted of by GRT/GE-500F/Po1y(2-EHA) and CRT/Poly(AM-SAS-AA)/poly(2-EHA) were improved within from four times to twenty times compared to the one oi the commercial products.