• Proceedings of the Membrane Society of Korea Conference
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• 1998.04a
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• pp.97-98
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• 1998

1. Introduction : Polypropylene(PP) membrane is widely used in the field of microfiltration and ultrafiltration. However, the hydrophobicity of PP causes the adsorption of hydrophobic and amphoteric solutes in the feed. Surface modification techniques of membrane through the treatment of hydrophilizing agents, coating of hydrophilic compounds, UV, plasma and high energy irradiation, etc. can have a great effect on propensities to prevent the protein from staining membranes. Among them, the modification to hydophilize membrane surface using UV is very simple and effective. Recently many studies for more effective surface modification have been conducted. Iwata et al. prepared membranes by grafting polyethylene glycol diacrylate macromer(PEGDA) onto polysulfone with plasma using a glow discharge reactor which prevent the oil from staining the membrane. The primary mechanism contributing to the membranes is preventing the oil from directly contacting the surface of the membrane as the PEGDA chains dissolved into emulsion. To evaluate their feasibility for use as a anti-fouling separation membrane, we prepared hydrophilic membranes by UV irradiation method and investigated their characteristics.

• Journal of the Korean Society of Clothing and Textiles
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• v.26 no.1
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• pp.144-151
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• 2002

The assessment of hand of the denim fabrics finished by enzymatic hydrolysis will be discussed in this study. The subjective hand and the preference of the denim fabrics finished by enzymatic hydrolysis were evaluated using the developed scale(Part I). The factors affecting consumer's taste for denim fabrics were analyzed by statistics using SAS program. Also, the enzymatic of hydrolysis on the properties of denim fabrics were evaluated by subjective hand measurements. The results are as follows; Regarding the surface properties and the weight, Tencel was evaluated to be the finest, the smoothest, the most flexible, the warmest, the most refined, the sleekest, the flossiest, the lightest the softest, and the thinnest among the four kinds of fabrics. The other fabrics in the order of cotton/Tencel, cotton, cotton/PP were evaluated to qualify the listed touches. Tencel was evaluated to be the loosest and the weakest among the four kinds of denim. Cotton was evaluated to have the driest touch. In addition, the fabrics were evaluated to be more elastic and less wrinkly in the order of Tencel > cotton > cotton/Tencel > cotton/ PP. For the hand preference, the fabrics were ranked in the order of Tencel, cotton, cotton/Tencel, cotton/PP, where tencel is the moat preferred. Cotton/Tencel and cotton/PP showed negative values in the hand and the color preference, meaning that the evaluators disliked their touches. Hand preference of enzyme hydrolyzed cotton/Tencel and cotton/PP denims do not seem to appeal to Korean people.

• IMMUNE NETWORK
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• v.5 no.4
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• pp.215-220
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• 2005

Background: Transforming growth factor-${\beta}$ (TGF-${\beta}1$) directs class switch recombination (CSR) to IgA isotype, which is a predominant antibody in mucosal surfaces. Although IgA is preferentially committed in mucosal lymphoid tissues, it is not definitely established whether hallmarks of IgA CSR such as IgA germ-line transcripts (GLT ${\alpha}$), post-switch transcripts (PST ${\alpha}$) and circle transcripts (CT ${\alpha}$) are readily expressed in such tissues. Therefore, we compared the expression of these transcripts among mouse Peyer's patches (PP), mesenteric lymph nodes (MLN), and spleen. Methods: Levels of GLTs, PSTs and CTs were measured by RT-PCR in isolated PPs, MLNs and spleen cells. Results: GLT ${\alpha}$ and PST ${\alpha}$ were well expressed in PP and MLN cells but in spleen cells. Similar patterns were observed in the expression of GL ${\gamma}$2b and PST ${\gamma}$2b. On the other hand, these transcripts were only inducible in spleen cells upon stimulated with LPS and TGF-${\beta}1$. In addition, CT${\alpha}$ and CT${\gamma}$2b were detected in PP cells. Conclusion: PP B cells readily express IgA GLT, PST, and CT. Overall expression patterns of these transcripts were similar in MLN cells. Thus, these results suggest that microenvironment of PP and MLN influences spontaneous IgA CSR, which lacks in systemic lymphoid tissues such as spleen.

• The korean journal of orthodontics
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• v.51 no.2
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• pp.115-125
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• 2021

Objective: To evaluate the reasons influencing the preferences for a certain type of orthodontic appliance over another among prospective patients (PP) and orthodontists. Methods: A total of 49 PP and 51 orthodontists were asked about their preferences for the following appliances: clear aligners (CA), lingual metallic brackets (LMB), polycrystalline and monocrystalline ceramic brackets, and buccal metallic brackets (BMB). The participants rated the importance of 17 potential reasons that would explain their choices. The reasons that contributed most to these preferences were identified. Non-parametric tests (Fisher's exact, χ2 and Mann-Whitney tests) and multivariate analyses (regression and discriminant analysis) were used to assess the data (α = 0.05). Results: CA and BMB were the most chosen appliances by PP and orthodontists, respectively. LMB was the most rejected option among both groups of participants (p < 0.001). Rates of the importance of pain/discomfort, smile esthetics, finishing details, and feeding/speech impairment showed the highest differences between PP and orthodontists (p < 0.0005). Discriminant analyses showed that individuals who considered treatment time and smile esthetics as more important were more likely to prefer CA, while those who prioritized finishing details and cost were more likely to choose BMB (p < 0.05). Conclusions: Reasons related to comfort and quality of life during use were considered as more important by PP, while those related to the results and clinical performance of the appliances were considered as more relevant by orthodontists.

• The Korean Journal of Pain
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• v.35 no.1
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• pp.86-96
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• 2022

Background: To explore the association between low back pain (LBP) and pelvic pain (PP) and rectus abdominis diastasis (RAD) in postpartum women and identify the characteristics and risk factors. Methods: Women diagnosed with RAD and a history of labor and delivery, between 2009 and 2018, were identified from six hospitals within the Partners Healthcare System. Univariate and multivariable binary logistic regression analyses were used to identify the risk factors associated with pain. Results: Age at onset of RAD in the non-cesarean delivery group was earlier than those in cesarean delivery (CD) group (P = 0.017). Women who underwent CD demonstrated 4.5 times greater risk of RAD than those who had no CD exposure. The cumulative composition ratio of LBP at every age stage of the period from 8 years pre-first delivery to 8 years post-first delivery was significantly higher than the other five conditions (RAD, umbilical hernia, PP, depressive disorder [DD], and strain of muscle, fascia, and tendon [SMFT]) (P for trend < 0.001). Women with DD, SMFT, and PP were more likely to have LBP (odds ratio [OR] = 1.91, 95% confidence interval [CI] 1.06 to 3.47, P = 0.032; OR = 4.50, 95% CI 1.64 to 12.36, P = 0.003; OR = 2.14, 95% CI 1.17 to 3.89, P = 0.013; respectively). Conclusions: In postpartum women with RAD, DD, SMFT, and PP were found to be risk factors contributing to the development of LBP. Race and LBP also played roles in the development of PP.

• Archives of Plastic Surgery
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• v.51 no.2
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• pp.156-162
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• 2024

Background Perioperative management in autologous breast reconstruction has gained focus in recent years. This study compares two pain management protocols in patients undergoing abdominal-based free flap breast reconstruction: a past protocol (PP) and a current protocol (CP)-both intended to reduce opioid consumption postoperatively. The PP entails use of a pain catheter in the abdominal wound and the CP consists of an intraoperative nerve block in addition to refinements in the oral pain management. We hypothesize that the CP reduces opioid consumption compared to PP. Methods From December 2017 to January 2020, 102 patients underwent breast reconstruction with an abdominal-based free flap. Two postoperative pain management strategies were used during the period; from December 2017 to September 2018, the PP was used which entailed the use of a pain catheter with ropivacaine applied in the abdominal wound with continuous distribution postoperatively in addition to paracetamol orally and oxycodone orally pro re nata (PRN). From October 2018 to January 2020, the CP was used. This protocol included a combination of intraoperative subfascial nerve block and a postoperative oral pain management regime that consisted of paracetamol, celecoxib, and gabapentin as well as oxycodone PRN. Results The CP group (n = 63) had lower opioid consumption compared to the PP group (n = 39) when examining all aspects of opioid consumption, including daily opioid usage in morphine milligram equivalents and total opioid usage during the stay (p < 0.001). The CP group had shorter length of hospital stay (LOS). Conclusion Introduction of the CP reduced opioid use and LOS was shorter.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.9
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• pp.5660-5667
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• 2014

The aim of this study was to assess the association of metabolic syndrome, metabolic syndrome score (MSS) and pulse pressure (PP) in Korean adults. The study subjects were Korean adults 20 years or older (n=5,889) who participated in the Korea National Health and Nutrition Examination Survey 2012. After adjusting for factors, such as year and gender and BMI, the mean PP increased with increasing MSS (MSS 0, $41.30{\pm}0.34mmHg$ and MSS 1, $42.16{\pm}0.31mmHg$ and MSS 2, $44.73{\pm}0.34mmHg$ and MSS, 3, $46.46{\pm}0.42mmHg$ and MSS 4, $48.62{\pm}0.58mmHg$ and MSS 5, $53.50{\pm}1.05mmHg$), and the mean PP for metabolic syndrome($47.25{\pm}0.34mmHg$) increased in comparison to Non-Metabolic syndrome ($42.77{\pm}0.19mmHg$). When logistic regression analysis was performed, the odds ratio (OR) of Hyper-PP (61> PP) for MSS 0 was 4.49 in MSS 1 (95% confidence interval[CI], 2.68-7.57) and 8.01 in MSS 2 (95% CI, 4.77-13.47) and 11.37 in MSS 3 (95% CI, 6.67-19.35) and 19.69 in MSS 4 (95% CI, 11.20-34.60) and 34.07 in MSS 5 (95% CI, 17.44-66.52), metabolic syndrome was associated with an increased Hyper-PP(OR 4.6, 95% CI, 2.0-10.4). Conclusion. These results suggest that an increase in MSS or metabolic syndrome might increase the pulse pressure.

• Microbiology and Biotechnology Letters
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• v.38 no.3
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• pp.278-282
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• 2010

In this study, the antibacterial activity and component analysis of Persicaria perfoliata extracts were investigated. MIC (Minimum Inhibitory Concentration) values of ethyl acetate fraction from P. perfoliata on Escherichia coli, Propionibacterium acnes, and Staphylococcus aureus were 0.25%, equally. The results showed that the antibacterial activity of the ethyl acetate fraction was the highest in the S. aureus and P. acnes. Ethyl acetate fraction from P. perfoliata extracts showed 5 bands in TLC and 8 peaks in HPLC (320nm). In HPLC chromatogram of ethyl acetate fraction, first main peak 2 (24.99%) and peak 3 (22.65%) were identified as quercetin-3-o-glucuronide and isoquercitrin in the order of elution time. Also, in HPLC chromatogram of deglycosylated fraction, main peak 2 (76.93%) was identified as quercetin in the order of elution time. And these components are very effective as antioxidants. Thus, these results indicate that extract/fractions of P. perfoliata can be applicable to new functional cosmetics for antioxidant, antibacterial activity.

• Journal of Sensor Science and Technology
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• v.7 no.6
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• pp.426-431
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• 1998

This paper describes electrochemical etch-stop characteristics in THAH/IPA/pyrazine solution. I-V curves of n- and p-type Si in THAH/IPA/pyrazine solution were obtained. OCP(Open Circuit Potential) and PP (Passivation Potential) of p-type Si were -1.2 V and 0.1 V, and of n-type Si were -1.3 V and -0.2 V, respectively. Both n- and p-type Si, etching rates were abruptly decreased at potentials anodic to the PP. The etch-stop characteristics in THAH/IPA/pyrazine solution were observed. Since accurate etching stop occurs at pn junction, Si diaphragms having thickness of epi-layer were fabricated. Etching rate is highest at optimum etching condition, TMAH 25wt.%/IPA 17vol.%/pyrazine 0.1g/100ml. thus the elapsed time of etch-stop was reduced.

• Elastomers and Composites
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• v.15 no.1
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• pp.3-9
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• 1980

The oxygen permeability and it's proofness of te various commercial polymer films have been investigated at the constant pressure and temperature. Oxygen proofness, the reciprocals of the oxygen permeability for the various samples, were determined by means of a coulometric oxygen permeability tester. The testing of sample films was performed at constant temperature $(23{\pm}1^{\circ}C)$ under 1 atm. for 24 hours. The order of the relative proofness observed are as follows; oriented Nylon (O. Nylon)> oriented Polyester (O. PET)>nonoriented Nylon (N. Nylon)>nonoriented Polyester (N.PET)> rigid Polyvinyl chloride (Rigid PVC)>semirigid Polyvinyl chloride (Semirigid PVC)> oriented Polypropylene (O. PP)>plasticized Polyvinyl chloride (P. PVC)> casted Polypropylene (C. PP)> low density Polyethylene (LDPE)>high density Polyethylene (HDPE, Inflation)> high density-polyethylene (HDPE, T-die) The oxygen proofness of the films was increased with the polarity cf polymer, the film thickness and mechanical orientation and decreased with the addition of plasticizer in PVC. For the use of wrapping materials, one film with the polar property in the main chain of the polymer molecule and the others with nonpolar property in it are laminated for the protection from oxygen and moisture.