• 전기화학회지
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• 제16권4호
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• pp.198-203
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• 2013

본 실험에서는 MMA와 tBMA의 공중합체를 합성하고, tert-butyl 그룹의 가수분해를 선택적으로 유도하여 poly(MMA-co-MA)를 제조하였다. 또한 말단에 에폭시기를 함유한 다양한 분자량의 PEO와 MA와의 grafting-onto 커플링 반응을 통해 같은 주사슬을 가지지만 부사슬의 길이가 다른 poly(MMA-co-PEGMA)를 합성하여 조성이 이온전도도에 미치는 영향을 평가하였다. AC-impedance로 측정한 상온 이온전도도는 MMA의 몰분율이 82%에서 $5.11{\times}10^{-8}Scm^{-1}$의 값이 얻어진 반면, 48%에서는 $1.88{\times}10^{-6}Scm^{-1}$로서 많은 PEGMA에서 높게 관찰되었다. 또한 에폭시기를 함유한 PEO의 분자량에 따라 이온전도도의 차이가 발생하는데, grafting-onto 법의 입체적 장애가 원인으로 고려되었다. 한편, 합성된 poly(MMA-co-PEGMA) 고분자 전해질은 상온에서 6V까지 우수한 전기화학적 안정성을 보여주었다.

• 폴리머
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• 제33권3호
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• pp.268-271
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• 2009

본 연구에서는 방사선 동시조사법에 의해 제조된 FEP-g-PSSA 막 단면을 SEM-EDX 기기로 분석하여 스티렌 술폰산 고분자(PSSA)의 막 내부로의 분포 경향을 연구하였다. 본 실험에서는 그래프트율, FEP 필름 두께, 선량률, 그래프팅 용매 등 여러 조사조건이 그래프트 고분자의 분포에 미치는 영향을 중점적으로 연구하였다. 실험 결과 균일하게 그래프트된 FEP-g-PSSA 막을 얻기 위해서는 필름 두께가 증가할수록 높은 그래프트율이 요구되어지고, 같은 조사 선량에서는 낮은 조사 선량률로 그래프트하는 것이 효과적임을 보여준다.

• 대한구순구개열학회지
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• 제4권2호
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• pp.69-78
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• 2001

Alveolar cleft exists in 75% of cleft patients, In alveolar cleft patients, alar base is widening, palatal fistular formation, maxillary growth disturbance & tooth loss of adjacent area is raised, Alveolar bone grafting, especially iliac bone grafting, is a general treatment method. As operation timing, bone grafting is classified with primary, early secondary, secondary, & late secondary, Here we report cleft width, marginal bone height, bone resorption rate, grafted shape & bone densities after secondary iliac bone grafting was done in the Dept. of oral and maxillofacial surgery of chonbuk national university hospital. We compared cleft width to bone resorption rate and grafted shape. Also, alveolar bone densities of grafted and contralateral site was compared with Emago 3 package? (Oral Diagonostic System, The Netherlands), The data obtained were analyzed using Spearman's rho coefficients and sign test with SPSS for window, The results were obtained as follows. 1. As alveolar cleft width is increase, bone resorption rate is, too. This relation showed significant difference(P<.01). 2, In proximal & distal area, alvolar cleft width and bone graft contour after bone grafting had a reverse proportional difference. It was not significant difference(P>.05). 3. After 3 month, in bone density results by using Emago 3 package? with periapical standard view, occlusal view & panoramic view, differences between grafted bone and alveolar bone of contralateral site didn't show a significant difference(P>.05). Thus, differences of bone densities in the alveolar bones didn't exist.

• 접착 및 계면
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• 제13권1호
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• pp.1-8
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• 2012

EPDM에 카르복시산을 포함하는 아크릴 단량체인 methacrylic acid (MA)가 도입된 grafted EPDM을 합성하여 MA의 grafting ratio가 탄성체의 물성과 다른 고무와의 접착특성에 미치는 영향을 연구하였다. Grafted EPDM의 storage modulus는 특정온도까지는 sulfur로 가교한 EPDM vulcanizate보다 높게 유지되다가 온도가 더 높아지면 2차 결합력이 약해지면서 급격하게 감소되는 것이 관찰되었다. EPDM에 수소결합을 유도할 수 있는 반응기를 도입했을 때 grafted EPDM 분자들 간의 aggregate 형성과 그라프트된 MA의 결정성으로 인해 우수한 기계적 물성을 나타내었다. EPDM 자체는 극성이 낮고 다른 종류의 고무와 분자간 결합력이 약해서 접착이 제대로 이루어지지 않았으며 그라프트된 MA의 함량이 증가할수록 접착강도가 더 높아졌으며 MA의 grafting ratio가 10% 이상일 때에는 접착평가 시 고무시편이 부분적으로 파괴될 정도로 접착력이 우수하였다.

• 한국자원식물학회지
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• 제18권1호
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• pp.78-84
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• 2005

3개의 고추 대목품종에 따라 접목의 효과를 알아보기 위하여 본 실험을 실시한 결과 R-safe 대목이 육묘상태에서 Yeok kang과 Konesian hot에 비해 초장과 초세가 양호하였으며 접목 작업시 접목 부위의 절간두께 및 길이, 수액이 나오는 정도가 접목하기에 적합 하였다. 접목을 한 처리구가 비 처리구에 비하여 분지수의 생육이 양호하였으며, 접목이 분지수 발생에도 영향을 나타냈다. 대목의 종류에 따른 초장 차이는 접목 후 7일째 까지는 차이가 없었고 접수에 따라 초장의 차이가 나타났으며, 접목 후 41일째 R-safe 대목을 이용한 처리구가 다른 처리구들에 비하여 초장의 신장성이 현저하였다. 접목한 처리구의 개화기가 빨랐으며 대목중에서 R-safe 품종이 조기 개화하여 저온신장성이 양호하였다.

• Archives of Plastic Surgery
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• 제45권1호
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• pp.69-73
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• 2018

Background Temporal hollowing is inevitable after decompressive craniectomy. This complication affects self-perception and quality of life, and various techniques and materials have therefore been used to restore patients' confidence. Autologous fat grafting in postoperative scar tissue has been considered challenging because of the hostile tissue environment. However, in this study, we demonstrate that autologous fat grafting can be a simple and safe treatment of choice, even for postoperative depressed temporal scar tissue. Methods Autologous fat grafting was performed in 13 patients from 2011 to 2016. Fat was harvested according to Coleman's strategy, using a tumescent technique. Patient-reported outcomes were collected preoperatively and at 1-month and 1-year follow-ups. Photographs were taken at each visit. Results The thighs were the donor site in all cases for the first procedure. The median final volume of harvested fat was 29.4 mL (interquartile range [IQR], 24.0-32.8 mL). The median final volume of fat transferred into the temporal area was 4.9 mL on the right side (IQR, 2.5-7.1 mL) and 4.6 mL on the left side (IQR, 3.7-5.9 mL). There were no major complications. The patient-reported outcomes showed significantly improved self-perceptions at 1 month and at 1 year. Conclusions Despite concerns about the survival of grafted fat in scar tissue, we advise autologous fat grafting for patients with temporal hollowing resulting from a previous craniectomy.

• 폴리머
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• 제36권1호
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• pp.65-70
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• 2012

글리시딜메타크릴레이트(GMA)의 플라즈마 유도 그래프트 공중합을 통해 기재로 사용한 평판형 폴리프로필렌 위에 에폭시 그룹을 도입하였다. 그래프트 공중합은 에멀젼 공중합법을 적용하였고, 기존의 용액 공중합과 비교하여 그 효과를 확인하고자 하였다. 대기압 플라즈마 처리 조건은 RF power 200 W, 처리시간 30초, Ar 기체 유속 6 LPM으로 고정하였고, 처리 후의 대기 중 노출시간 역시 5분으로 고정하였다. 중합반응에서는 GMA의 농도, 반응온도, 반응시간에 따라 표면 그래프트도의 변화를 최적화하였다. 그 결과, GMA 농도 12%, 반응온도 $90^{\circ}C$, 반응시간 5시간으로 중합하였을 때 가장 높은 그래프트도를 나타내었다. 분석 결과, 같은 반응조건 하에서 에멀젼 중합이 용액 중합에 비하여 더 많은 에폭시 그롭 도입에 효과적임을 확인하였다.

• Archives of Plastic Surgery
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• 제49권5호
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• pp.614-616
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• 2022

As of November 2021, TikTok has one billion monthly active users and is recognized as the most engaging social media platform. TikTok has seen a surge in users and content creators, ranging from athletes to medical professionals. In the past year, content creators have utilized the app to advocate for social reforms, education, and other uses that were not previously considered. Breast cancer is the most commonly diagnosed cancer in women, with an expected 281,550 new cases of invasive breast cancer in 2021. As more individuals with breast cancer choose to undergo resection, the demand for autologous fat grafting in breast reconstruction has increased due to the natural look and feel of breast tissue. The purpose of this article is to analyze content related to breast reconstruction with fat grafting found on TikTok and recommend methods to improve patient education, care, and outcomes. We searched TikTok on November 1, 2021, for videos using the phrase "breast reconstruction with fat grafting." The top 200 videos retrieved from the TikTok search algorithm were analyzed, and all commentaries, duplicates, and nonrelevant videos were removed. Video characteristics were collected, and two independent reviewers generated a DISCERN score A total of 131 videos were included in the study. They were found to have a combined 1,871,980 likes, 41,113 comments, and 58,662 shares. The videos had an average DISCERN score of 2.16. Content creators had an overall low DISCERN score in items involving the use of references, disclosure of risks for not obtaining treatment, and support for shared decision-making. When stratified, the DISCERN score was higher for videos created by physicians (DISCERN average 2.48) than for videos created by nonphysicians (DISCERN average 1.99; p < 0.001).

• BMB Reports
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• 제49권12호
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• pp.655-661
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• 2016

Polymer brush is a soft material unit tethered covalently on the surface of scaffolds. It can induce functional and structural modification of a substrate's properties. Such surface coating approach has attracted special attentions in the fields of stem cell biology, tissue engineering, and regenerative medicine due to facile fabrication, usability of various polymers, extracellular matrix (ECM)-like structural features, and in vivo stability. Here, we summarized polymer brush-based grafting approaches comparing self-assembled monolayer (SAM)-based coating method, in addition to physico-chemical characterization techniques for surfaces such as wettability, stiffness/elasticity, roughness, and chemical composition that can affect cell adhesion, differentiation, and proliferation. We also reviewed recent advancements in cell biological applications of polymer brushes by focusing on stem cell differentiation and 3D supports/implants for tissue formation. Understanding cell behaviors on polymer brushes in the scale of nanometer length can contribute to systematic understandings of cellular responses at the interface of polymers and scaffolds and their simultaneous effects on cell behaviors for promising platform designs.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 2000년도 THE THIRD INTERNATIONAL CONFERENCE ON AGRICULTURAL MACHINERY ENGINEERING. V.III
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• pp.632-638
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• 2000

This paper represents the characteristics of evapotranspiration rate (EVTR) and graft-taking of watermelon grafted seedlings in a graft-taking enhancement system using fluorescent lamps as artificial lighting source. Four air temperature levels of 23, 25, 27 and 29C, three humidity levels of 85, 90 and 95%R.H. and two photosynthetic photon flux (PPF) levels of 30 and 50 ${\mu}$mol m$\^$-2/ S$\^$-1/ were provided to investigate the effects of air temperature, relative humidity and light intensity on EVTR and graft-taking of grafted seedlings. EVTR of grafted seedlings increased with increasing air temperature and the passage of time after grafting. Also EVTR increased with decreasing relative humidity. As relative humidity decreased and air temperature increased, vapor pressure deficit increased and thus EVTR increased. It is required to maintain a low level vapor pressure deficit for suppressing EVTR of grafted seedlings during first 1-2 days after grafting. Therefore, less EVTR at initial stage after grafting would be adequate for smooth joining of the scion and rootstock.