• Journal of the Korean Arthroscopy Society
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• v.12 no.2
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• pp.125-128
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• 2008

Purpose: The object of this study is to compare the clinical results of noraml saline and Lactated Ringer's solution in the arthroscopic meniscus surgery on the knee. Materials and Methods: The study group included 64 patients who had an medial meniscus tear and received arthroscopic partial medial meniscectomy. The group I was normal saline group, which was used as an irrigation solution during operation. The group II was Lactated Ringer's solution group. We measured the visual analogue scale, painless active knee flexion angle, and the ratio of the knee swelling at postoperative one day for all patients. Results: The visual analogue scale and the painless active knee flexion angle were no significant differences in comparing with normal saline and Lactated Ringer's solution group. The ratio of the knee swelling in Lactated Ringer's solution group was significantly less than those of noraml saline group. Conclusion: Lactated Ringer's solution has an advantage of decreasing the knee swelling in the arthroscopic meniscus surgery on the knee.

• Journal of Physiology & Pathology in Korean Medicine
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• v.16 no.2
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• pp.272-278
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• 2002

To investigate the anti-inflammatory and analgesic effects of Herba Chelidoniie, the extracts of Herba Chelidoniie treated in arthritic rat model. Complete Freund,s Adjuvant(CFA) were injected in the subcutaneous tissue of left foot paw of rats to induce arthritis. Herba Chelidonii extracts(HC) was administered immediately into the peritoneal cavity after CFA injection for 12 days. The immunohistochemical stainings for calcitonin gene-related peptide(CGRP) and substance P in the L4, L5 and L6 spinal dorsal horn and ganglia were done, and the paw swelling was measured with a micrometer and the blood leukocytes were counted. The results were as follows : The paw swelling of HC treated group was significantly decreased in 12th day after CFA injection compare to control group. The change of differential leukocytes counts of HC treated group increased the ratio of lymphocytes, and decreased the ratio of neutrophils compare to control group. The extent of CGRP immunoreactive nerve fiber of dorsal horn of HC treated group was weakly stained compare to control group. The number of CGRP immunoreactive neurons of L6 spinal cord of HC treated group was significantly decreased compare to control group. The extent of substance P immunoreactive nerve fiber of dorsal horn of He treated group was weakly stained compare to control group. The number of substance P immunoreactive neurons of L4, L5 and L6 spinal cord of HC treated group was significantly decreased compare to control group. These experimental results suggest that Herba Chelidonii extracts reduce the number of CGRP and substance P immunoreactive neurons and nerve fibers of spinal dorsal horns and ganglia, and decrease paw swelling in arthritic rat model, which may be closely related to analgesic and antiinflammatory effects of Herba Chelidonii.

• Clinics in Shoulder and Elbow
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• v.15 no.2
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• pp.109-116
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• 2012

Purpose: The aim of this study was to evaluate preoperative ultrasonographic findings and usefulness in ulnar neuropathy around elbow. Materials and Methods: Twenty-two patients with ulnar neuropathy were performed preoperative ultrasonogram. The route, location, thickness of the ulnar nerve and space occupying lesion through longitudinal scan were evaluated. Cross-sectional areas of the ulnar nerve were measured at the level of medial epicondyle and 3 cm proximal and distal to the medial epicondyle through axial scan. Correlations between swelling ratio of ulnar nerve and eletrophysiologic study and preoperative Dellon's assessment were checked. Results: In 21 cases (95.6%) of total 22 cases, diffuse swelling of the ulnar nerve around elbow were identified. 4 cases had space occupying lesions including 3 ganglionic cysts and 1 heterotopic ossification. Cross sectional areas at the level of medial epicondyle were significantly larger than at the level of 3 cm proximal and distal to the medial epicondyle (p<0.05). There were no statistically significant correlations between swelling ratio of ulnar nerve and eletrophysiologic study and preoperative clinical assessment (p>0.05). Conclusion: This study showed that ultrasonography was helpful to detect etiology of ulnar neuropathy around elbow such as space occupying lesion, morphological change or dislocation of ulnar nerve. It could be useful tool for diagnosis and treatment in patients with ulnar neuropathy at elbow.

• Polymer(Korea)
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• v.33 no.5
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• pp.469-476
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• 2009

In this study, biodegradable superporous hydrogels(SPHs) with fast swelling and superabsorbent properties were prepared using biodegradable crosslinkers and their physicochemical properties were characterized. A biodegradable crosslinker (PLA-PEG-PLA DA) was synthesized by a ring opening polymerization of D,L-lactide (LA) using hydrophilic poly(ethylene glycol) as a macroinitiator, followed by diacrylation of the end groups for the introduction of polymerizable vinyl groups. Various kinds of hydrogels with different chemical compositions were prepared and characterized in terms of swelling ratio, swelling kinetics, and biodegradation properties. The synthetic results were confirmed by $^1H$-NMR, FT-IR and GPC measurements, and the porous structures of the prepared SPHs and their porosities were identified by a scanning electron microscope and mercury porosimetry, respectively. The physicochemical properties of SPHs could be controlled by varying their chemical compositions and their cytotoxicity were found to be very low by MTT assay.

• Journal of Forest and Environmental Science
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• v.31 no.2
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• pp.119-125
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• 2015

This study examined the effects of rice straw steaming time and mixing ratio between rice straw and wood particle on the properties of mixed particle board from Acacia mangium Willd wood and rice straw. Rice straw and Acacia mangium Willd wood were collected in Hanoi, Vietnam. The particle board was three-layer particle board with the structural ratio of 1:3:1. The thickness, density and board size of the particle board were 18 mm, $0.7g/cm^3$, and $800{\times}800{\times}18$ (mm, including trimming), respectively. A resin mixture between commercial Urea-formaldehyde (U-F) adhesive and methylene diphenyl isocyanate (MDI) adhesive was used with a dosage of 12% for the core layer and 14% for the surface layer. In this experimental design, the steaming time for rice straw was 15, 30, 45, 60, and 75 minutes at $100^{\circ}C$. The rice straw-wood mixing ratio was 10, 20, 30, 40, and 50%. The results showed that both mixing ratio and steaming time affect the properties of the particleboard, but the mixing ratio has a stronger impact. A higher mixing ratio and a longer steaming time resulted in a better quality of particleboard. The optimal steaming time for rice straw was 46.12 minutes with the straw-wood mixing ratio of 29.85% with the following characteristics of the particle board: the modulus of rupture (MOR) of 14.64 MPa, internal bond strength (IB) of 0.382 MPa, thickness swelling (TS) of 8.83%, and board density of $0.7-0.7g/cm^3$.

• Land and Housing Review
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• v.12 no.4
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• pp.127-137
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• 2021

Grouting has been widely used to enhance the strength of the ground and prevent waterflow into the underground space in the geotechnical engineering field. Cement with bentonite can be considered a helpful grouting material because the bentonite has a swelling ability with water. Therefore, it is essential to evaluate the characteristics of grouting materials according to the mixing ratio for a successful grouting process. In this regard, the study investigated the viscosity and bleeding characteristics of grouting materials according to the mixing ratio (i.e., water/cement ratio and bentonite/cement ratio). In the experimental result, the viscosity increases with decreasing water/cement ratio and rising proportion of bentonite by weight of cement. However, the results of the bleeding ratio show the tendency is inversely proportional to the viscosity results. Bentonite was explored in terms of the viscosity and bleeding criterion. This result is expected to be meaningful to determine the optimized mixing ratio of bentonite-cement in the grouting field.

• Journal of the Korean Wood Science and Technology
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• v.28 no.3
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• pp.1-8
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• 2000

To develop the technology of producing structural board from low grade materials, an attempt was made to produce strand/particle composites from split wood strand(S) and particle(P) of (Cryptomeria japonica D. Don), which changed the layer construction and the ratio of S/P. The influence of layer construction on board properties was determined, focusing on the number and alignment of the S layers. The effect of weight ratio of S/P (3:7, 1:1, 7:3) on mechanical properties was also discussed on seven layered panel. Mechanical properties were determined from static bending tests to give parallel and perpendicular modulus of rupture (MOR) and modulus of elasticity (MOE), and the internal bond (IB) strength. In general, the surface strand layers contributed to the MOR and MOE. The parallel MOR and MOE values were the largest for the single layered S panel (only Slayers: S1), but the perpendicular MOR and MOE was the smallest. Perpendicular MOR and MOE were the largest for seven layered composite that had two cross oriented strand layers (SPSPSPS: SP7). Specimens retained more than half of their MOE and MOR after two hours in boiling water and one hour soaking. IB was the largest for the panel having only P layers, however, differences in IB strength were not identified among the other multi-layered composite panels thus the effect of layer construction on IB strength was small. Thickness swelling (TS) and surface roughness were smaller for the composite having P layers on the surface than for those having S layers. The addition of strands did not enhance the mechanical properties (MOR, MOE, IB). TS values for the panels, with which the S/P ratio was over than 1:1, was the similar to the value for the single layered S panels.

• Applied Chemistry for Engineering
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• v.16 no.3
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• pp.397-402
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• 2005

Core-shell Poly(styrene-co-N-isopropylacrylamide) (poly(St-co-NIPAm) was prepared by soap-free emulsion polymerization of styrene (St) and N-isopropylacrylamide (NIPAm) in aqueous solution with potassium persulfate (KPS) as an initiator. The effects of St/NIPAm ratio, concentrations of monomer and crosslinker were studied. Also, Thermo sensitivity of microgels prepared was investigated. Particle size of microgels increased with increasing mol ratio of NIPAm to styrene. Transmittance of the microgel dispersion decreased rapidly when heated above a low critical solution temperature (near $32{\sim}34^{\circ}C$, cloud point). Swelling ratio of the microgel increased with increasing of the concentration of monomer (NIPAm) and decreased proportional to the concentration of crosslinker.

• Fashion & Textile Research Journal
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• v.8 no.5
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• pp.577-584
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• 2006

The binding of heavy metal ions onto cross-linked chitosan in dilute aqueous solution has been investigated as a function of pH (4.0 and 7.0), agitation period (10-180min) and concentration of various metal cations (5, 10, 50 and 100ppm). In order to obtain adsorbents that are insoluble and stable, and prevent the dissolution loss of chitosan into an acidic aqueous solution, chitosan flakes were cross-linked with epichlorohydrine (ECH) and its adsorption behavior was compared with that of the non cross-linked chitosan. An advantage of ECH is that it does not eliminate the cationic amine functional group of chitosan. In terms of adsorption ratio, the chitosan cross-linked at an ECH was inferior to original chitosan and was found that chitosan has a selectivity much remarkable than the cross-linked chitosan in low concentrated metal solutions. However, no significant decreases in the adsorption ratios were observed between the cross-linked ECH-chitosan and the non cross-linked chitosan concerning the adsorption of $Ni^{2+}$, $Co^{2+}$, $Pb^{2+}$ and $Zn^{2+}$ acidic solution.

• Journal of the Korean Society of Clothing and Textiles
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• v.13 no.4
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• pp.427-436
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• 1989

Poly (vinyl alcohol) films, which .were annealed at various different annealing conditions, were carried out by uniaxial stretching them with free width in water and were investigated drawing behaviours and rupture phenomena. l) After dipping the specimen into the water, it took about 15 min. for the specimen's swelling to approach to equilibrium. 2) When the film annealed at $180^{\circ}C$ for 10 min. was drawn at $20^{\circ}C$. it was shown very toughness. 3) By means of birefringence measurements, the total molecular orientation of the annealed films increased until the draw ratio of 4, but drawing them above the draw ratio of 5, that of untreated films increased. 4) In the case of the mechanical properties of the drawn films. the annealed films tended to good trend for the draw ratios between 1 and 4. but drawing them above the draw ratio of 5. the untreated films tended to good trend for them.