• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.31 no.4
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• pp.76-83
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• 1999

This study was carried to investigate optimum conditions of charcoal added paper in making cigarette filter for the removal of smoke contents of cigarettes. We investigated the physical properties of charcoal added paper according to the ratio of pulps, the amounts of characoal , the weight of sheets and crimping conditions in dry method, and then analyzed the smoke contents of cigarettes. The results obtained were as follows. 1. Sw-BKP was higher than Hw-BKP in methylene blue absorption by UV test. 2. Charcoal had an effect on stiffness for decreasing factor greatly , while the addition amounts of Sw-BKP and high weigth of sheets increased it, and the interaction of weight of sheets and charcoal was higher than other factors. 3. Tear index decreased by charcoal addition greatly, on the other hand high weight of sheets and Sw-BKP/Hw-BKP ratio increased ter, and the interaction of pulps and chacoal acted on major factors. 4. We estimated crimp index with sensory evaluation , and charcoal hand an effect on decreasing factor in crimping greatly, while the interaction of weight of sheets and pulp ratio was higher than others. 5. In the case of charcoal added paper filter, tar removal efficiency of smoke contents was higher but about 6% than cigarette filter. Especially vapour phase(aldehyde) in smoke contents was removed greatly.

• Safety and Health at Work
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• v.11 no.4
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• pp.485-490
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• 2020

Background: Meniscal tears are among the major risk factors for knee osteoarthritis progression. This study aimed to investigate the relationship between meniscal tears and work-related factors in the farming occupation. Methods: The participants included 486 farmers (238 men and 248 women), aged 40-69 years, who were among the 550 farmers registered in the Korea Farmer's Knee Cohort (KFKC). Data such as those on gender, age, body mass index (BMI), mechanical axis, cumulative heavy-lifting working time (CLWT), cumulative squatting working time (CSWT), and previous knee injury history were collected from the questionnaire, along with whole leg radiographic findings. Two radiologists assessed the magnetic resonance images of both knees to confirm the presence of meniscal tears. The factors related to meniscal tears were analyzed by multiple logistic regression. Results: A total of 54.5% of the farmers (48.7% of men and 60.1% of women) had meniscal tears. These tears were associated with gender, age, and BMI. We also identified an association between meniscal tears and CSWT, an especially important factor in farming [10,000-19,999 working hours, odds ratio = 2.16, 95% confidence interval (CI): 1.14-4.07, ≥20,000 working hours, odds ratio = 2.35, 1.45-3.80]. However, mechanical axis, knee injury history, and CLWT were not significantly related to meniscal tears. Conclusion: This study's findings show that squatting for long periods, as an occupational factor, is related to meniscal tears.

• Clinics in Shoulder and Elbow
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• v.11 no.2
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• pp.96-103
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• 2008

Purpose: This study investigated the rate of retear and related factors after arthroscopic repair of rotator cuff tears involving more than one tendon. Materials & Methods: Arthroscopic repair of 22 rotator cuff tears (average size 3.2cm: average age 58 years old) involving the supraspinatus and part or all of the infraspinatus were investigated using MRI on average 10 months after repair. The status of the repaired cuff was investigated using Sugaya's classification, and the change in muscle was evaluated with Goutallier's classification. Results: Retear (Sugaya grade IV, V) was found in 7cases(32%). Tears larger than 3cm had a higher retear rate(67%) than smaller tears(8%). Retear cases had Goutallier grade II or higher muscle changes preoperatively and showed aggravation of muscle atrophy postoperatively. Even without retear, reversal of muscle change was not seen Conclusion: Rotator cuff tears not confined to the supraspinatus had a 32% retear rate after arthroscopic repair. The size of the tear was the most crucial factor influencing retear. Retear was frequent in tear over 3cm. Atrophy of the cuff muscle worsened when the repair failed but did not improve even without retear.

• Journal of Veterinary Clinics
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• v.18 no.4
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• pp.418-423
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• 2001

To investigate the modulation of nerve growth factor (NGF) during corneal epithelial wound healing and the effect of topical NGF on corneal epithelial wound healing in dogs. An axial epithelial defect was created in the right eye using 6mm axial corneal mechanical debridement while the left served as an unwounded control. The tears were collected from both eyes during 1 week and the corneal epithelium was processed for the measurement of NGF at day 0 and 7. The NGF content of tears and corneal epithelium was determined by enzyme-linked immunosorbent assay. In another experiment, the animals were divided into 3 groups. The right eyes in each group were treated every six hours with 200 ug/ml of recombinant human (rh) NGF, murine NGF, or 600 ug/ml of anti-NGF blocking antibody. The left eye of each animal was treated with bovine serum albumin (BSA) to serve as controls. Wound healing was analyzed using NIH image software. Tear NGF was markedly increased in the wounded eyes, relative to tears from control eyes during the early healing period. The NGF content of the corneal epithelium was elevated in the wounded eye (p=0.024). Time to wound closure and rate of epithelial migration were not significantly different between the NGF treated or the NGF antibody treated, and the control BSA treated eyes. Corneal epithelial wounding increased NGF content only on the wounded side during the early healing period. Neither topical recombinant human or murine NGF affected corneal epithelial wound healing in the normal dog.

• Clinics in Shoulder and Elbow
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• v.1 no.2
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• pp.250-255
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• 1998

Purpose of the study was to analyze the supraspinatus outlet image of sagittal MRI in rotator cuff disease. We analyzed the sagittal views of the shoulder MRI of 78 cases without cuff tear. The cases were divided into 51 cases of rotator cuff disease group and 27 cases of control group. Six parameters of acromial tilt, coracoacromial ligament angle, length and height of coracoacromial triangle, length of acromial side of the baseline and distance of intrusion of the humeral head were compared for each group. The distance of intrusion of the humeral head was the most significantly different one, 0.52cm for rotator cuff disease group and 0.15cm for control group. Intrusion of the humeral head to the supraspinatus outlet space from the bottom may be a contributing factor developing rotator cuff disease. The intrusion may precede to tearing of the rotator cuff.

• Fashion & Textile Research Journal
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• v.15 no.3
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• pp.452-460
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• 2013

This study conducted a performance evaluation of protective clothing materials used for welding in a hazardous shipbuilding industry work environment. The welding process was selected as the one that most requires industrial protective clothing according to work environment characteristics. Flame proofing and convection heat protection performance (HTI) in the heat transfer characteristics of protective clothing material were indicated in the order of SW1(Oxidant carbon)>SW2(silica coated Oxidant carbon)>SW4(Oxidant carbon/p-aramid)>SW3(flame proofing cotton). However, radiant heat protection performance (RHTI) and the heat transfer factor (TF) were indicated in the order of SW1>SW4>SW2>SW3 and showed different patterns from the convection heat protection performance. SW1 showed superior air permeability and water vapor permeability. The tensile strength and tear strength of welding protective clothing material were indicated in the order of SW4>SW2>SW3>SW1 and showed that a blend fabric of p-aramid was the most superior for the mechanical properties of SW4. SW1 had excellent heat transfer properties in yet met the minimum performance requirements of tensile strength proved to be inappropriate as being a material for welding protective clothing. The abrasion resistance of woven fabric proved superior compared to nonwoven fabric; however, seam strength and dimensional change both met the minimum performance requirements and indicated that all samples appeared non-hazardous. Finally, oxidant carbon/p-aramid blend fabric appeared appropriate as a protective clothing materials for welding.

• Polymer(Korea)
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• v.32 no.3
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• pp.270-275
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• 2008

Crack growth characteristics of elastomeric materials are an important factor determining the strength and durability. In this study, the fatigue crack growth characteristic of filled EPDM compounds with different reinforcing fillers, such as silica and carbon black, was investigated using a newly designed tester. Frequency and test temperature had significant effects on the fatigue crack growth. The crack growth rate decreased with increasing frequency and the rate increased with increasing temperature. A power law relationship between the tearing energy and crack growth was observed for filled EPDM compounds. The crack growth rate reduced with increasing filler contents. Silica filled EPDM showed a better fatigue resistance than carbon black filled EPDM. The crack growth rate of silica filled EPDM decreased up to 30 phr and increased again at 50 phr. The formation of microductile type pits was observed on the fatigue-failure surface of unfilled EPDM, and relatively coarse surface with randomly distributed tear lines was observed on the failure surface of silica filled EPDM.

• Journal of Fashion Business
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• v.16 no.6
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• pp.21-35
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• 2012

In consideration of the injuries and deaths occurring at manufacturing sites due to the use of inappropriate work clothes or safety devices, this study aims to categorize manufacturing work processes to develop functional work clothes for heavy industries including the automobile, machine and shipbuilding industries in South Korea. Defining the features of the work environments and work postures of these industries provided for a categorization of the work processes which would enable the development of suitable work clothes for each work process' category. The results of the study based on a questionnaire survey are as follows: Work process category 1, including steel panel pressing and auto body assembly, final inspection (in automobile) and inspection (in machine), requires work clothes with upper body and arm mobility and performance to protect from the toxic fume factor. Work process category 2, consisting of welding (in automobile), cutting-and-forming (in machine) and attachment-and-construction (in shipbuilding), requires clothing elasticity, durability and heat and fire resistance. Work process category 3 comprising welding and grinding in the machine and shipbuilding industries, requires work clothes' tear resistance and elasticity, particularly for lateral bending mobility, and work clothes' sleeves' and pants' hemlines with sealed designs to defend against iron filing penetration, as well as incombustible and heat-resistant material performance. Finally, work process category 4, including painting in machine and shipbuilding, requires work clothes with waterproofing, air permeability, thermal performance, elasticity, durability and abrasion resistance.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.45 no.6
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• pp.30-35
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• 2013

To conserve wood resources for papermaking, chemical compositions of the hemp (Cannabis sativa L.) bast fiber cultivated in Korea such as holocellulose, ${\alpha}$-cellulose, lignin, alcohol-benzene extractives, hot and cold water extractives, and ash contents were investigated to manufacture the specialty packaging paper effectively. Significantly very low klason lignin content of 3.3% was accomplished by removing of the outer shell of bark. Laboratory soda pulping method which is very useful for the nonwood fiber was adapted, and it was found that there was no significant difference in both kappa number and H-factor between 25% and 30% NaOH charge. Hemp pulp cooked with the laboratory digester in 25% NaOH at $170^{\circ}C$ were mixed together with the wood pulp(NBKP:LBKP=1:1) in order to find the optimum mixture ratio which exhibited acceptable paper strength properties such as tensile index, burst index, and tear strength. When 10% of hemp soda pulps was mixed with 90% of wood pulps comprised of SwBKP and HwBKP (1:1), all physical strength increased significantly. The physical strength decreased as the amount of hemp pulp increased because the cell wall of bast fiber is very thick which causes low conformability and low fiber-fiber bonding. These results showed that paper made of hemp-wood pulp can be used for the specialty packaging paper which requires both the characteristic surface properties and the high physical strength of hemp fiber.

• Korean Journal of Exercise Nutrition
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• v.23 no.4
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• pp.14-22
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• 2019

[Purpose] Here, we aimed to determine the effect of Polygonum cuspidatum stem extract (PSE) on exorbital lacrimal gland-excised rat models and hyperosmotic stress-stimulated human conjunctival cells (HCCs). [Methods] Seven week old male Wistar rats were divided into six groups. Only the rats in the control group (NOR, n=5) did not undergo surgery. Three days after the surgery, the exorbital lacrimal gland-excised rats were randomly allocated to five groups: (1) vehicle-treated dry-eyed rats (DED, n=5); (2) PSE (10 mg/kg) treated DED rats (PSE-10, n=5); (3) PSE (100 mg/kg) treated DED rats (PSE-100, n=5); and (4) PSE (250 mg/kg) treated DED rats (PSE-250, n=5). In addition, the HCC line was co-treated with hyperosmolar media (528 mOsm) and PSE (1-100 μg/ml). [Results] PSE treatment restored the tear volume and goblet cell density by inhibiting severe corneal irregularities and damage. The treatment with PSE significantly attenuated the hyperosmolar stress-induced inflammation and cell death through the suppression of mRNA expression levels of Tumor necrosis factor-α (TNF-α), Interleukin-6 (IL-6), Interleukin-1β (IL-1β), and Interferon-γ (IFN-γ), and the expression of Bcl-2-associated X protein (Bax) as well as the activation of caspase-3 in vitro. [Conclusion] The inhibitory effects of PSE treatment on dry eye disease indicate the potential of nutritional intervention by PES against inflammatory diseases without adverse effects.