• Journal of Dairy Science and Biotechnology
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• 제36권2호
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• pp.81-94
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• 2018

This review discusses the characteristics of major lignans and related studies and provides a basis for future studies. Lignans are present in various food products consumed daily, such as flaxseed and other seeds, vegetables, fruits, and beverages including coffee, tea, and wine. Lignans are natural phytoestrogens with a structure similar to that of secoisolariciresinol (Seco), mataireinol (Mat), pinoresinol (Pin), medioresinol (Med), lariciresinol (Lari), and syringaresinol, which is then converted to enterodiol (END) and enterolactone (ENL), which are mammalian lignans and the primary biologically active enterolignans, by the intestinal microflora. The associations between lignans and a decreased risk of cardiovascular disease are promising; however, they are not yet well-established, probably owing to low lignan intake in habitual Western diets. Nonetheless, these associations were more prominent at the higher doses in interventional studies. Many studies on humans and animals have reported the benefits of lignan consumption in protecting against CVD and metabolic syndrome by reducing lipid and glucose concentrations. END and ENL reportedly exert protective effects including phytoestrogenic, antioxidant, anti-inflammatory, and anticancer effects through various mechanisms. Moreover, lignans reportedly exert beneficial effects in breast, colon, and prostate cancer and osteoporosis have reported that. However, future studies are required to confirm the association between lignan and disease.

• 공업화학
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• 제9권4호
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• pp.463-468
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• 1998

알루미늄의 부식에 있어서 HCI 용액내에 황산을 첨가하는 경우 황산이온의 화학적 흡착에 의한 부식억제 효과가 나타나며, CV (cyclic voltammetry) 실험결과 황산이온은 핏트내부에 보호성 산화피막을 생성함으로서 에치핏트가 핏트내부와 알루미늄 표면에 함께 생성되어 핏트의 밀도가 증가하였다. 알루미늄 교류에칭시에 핏트분포는 황산이온의 농도와 환원전류량에 의하여 크게 영향을 받으며, 환원전류인가시 $0.8mC/cm^2$ 이하의 전하량에서 핏트내부에 생성된 산화피막은 황산이온 농도의 증가에 따라 핏트발생에 대한 저항성이 중가하였으나, $0.8mC/cm^2$ 이상에서는 산화피막내에 국부적인 구조변화가 발생하며 황산이온 농도에 관계없이 산화피막의 파괴가 빠르게 진행되었다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
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• pp.630-630
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• 2013

Recently, atomically smooth hexagonal boron nitride(h-BN) known as a white graphene has drawn great attention since the discovery of graphene. h-BN is a III-V compound and has a honeycomb structure very similar to graphene with smaller lattice mismatch. Because of strong covalent sp2bonds like graphene, h-BN provides a high thermal conductivity and mechanical strength as well as chemical stability of h-BN superior to graphene. While graphene has a high electrical conductivity, h-BN has a highly dielectric property as an insulator with optical band gap up to 6eV. Similar to the graphene, h-BN can be applied to a variety of field, such as gate dielectric layers/substrate, ultraviolet emitter, transparent membrane, and protective coatings. However, up until recently, obtaining and controlling good quality monolayer h-BN layers have been too difficult and challenging. In this work, we investigate the controlled synthesis of h-BN layers according to the growth condition, time, temperature, and gas partial pressure. h-BN is obtained by using chemical vapor deposition on Cu foil with ammonia borane (BH3NH3) as a source for h-BN. Scanning Transmission Electron Microscopy (STEM, JEOL-JEM-ARM200F) is used for imaging and structural analysis of h-BN layer. Sample's surface morphology is characterized by Field emission scanning electron microscopy (SEM, JEOL JSM-7100F). h-BN is analyzed by Raman spectroscopy (HORIBA, ARAMIS) and its topographic variations by Atomic force microscopy (AFM, Park Systems XE-100).

• 대한두개안면성형외과학회지
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• 제13권1호
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• pp.46-49
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• 2012

Purpose: The forehead flap is the workhorse in nasal reconstruction, which provides a similar skin color, texture, structure, and reliability. There are some disadvantages, including donor site morbidities, 2- or 3-stage operations, and postoperative management after initial flap transfer. Furthermore, there has been little attention to the exposed raw surface wound, after the first stage of an operation. This article describes the authors' modification to overcome this problem, using artificial collagen membrane. Methods: An Artificial collagen membrane is composed of an outer silicone membrane and an inner collagen layer. After a forehead flap elevation, the expected raw surface was covered by an artificial collagen membrane with 5-0 nylon suture. A simple dressing, which had been applied to the site, was changed every 2 or 3 days in an outpatient unit. At 3 weeks postprocedure, a second stage operation was performed. Results: With biosynthetic protection of the raw surface, there were no wound problems, such as infection or flap loss. Thus, the patient was satisfied due to an effortless management of the wound and a reduction in pain. Conclusion: The application of an artificial collagen membrane to the raw under-surface of the flap could be a comfortable and a protective choice for this procedure.

• 한국항만경제학회지
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• 제26권2호
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• pp.119-138
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• 2010

본 연구는 1984년 해운산업합리화 조치와 2009년 해운산업 구조조정과 경쟁력 강화 방안에 대한 정책의 특성을 비교하고 분석했다. 본 연구에 따르면 두 정책의 시행 주체와 목표, 그리고 정책 내용 등에서 상당한 차이를 보였다. 1984년에는 정부 주도하의 강력한 행정의지에 의해 선사 통폐합이 이뤄졌으나, 2009년에는 채권단에 의해 선사의 구조조정이 추진됐다. 위기 극복을 위한 처방에서도 각각 선사 통폐합과 선사 구조조정이라는 점이 서로 다른 특성이다. 1984년 해운산업합리화 조치는 우리나라 해운산업의 체질을 개선한다는 보다 근본적이고 적극적인 목표를 갖고 정책이 마련됐다면, 2009년 해운산업 구조조정과 경쟁력 강화 방안은 선사들의 도산을 막아 해운산업을 유지시키는 다소 한정적 접근이 담겨있다고 볼 수 있다.

• 한국어류학회지
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• 제21권2호
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• pp.87-92
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• 2009

논에 서식하는 미꾸라지의 등, 체측, 후두부 피부조직에 대한 조직학적 연구를 통해 계절변화에 따른 점액세포의 변화여부를 조사하였다. 계절이 변화함에 따라 표피조직의 일반적인 형태에는 변화가 없었으나 상피조직에 존재하는 점액세포의 단위면적당 개수와 크기가 유동적으로 변화하였다. 비록 점액세포의 발달정도는 겨울철에 크게 증가하고 여름철에 감소하는 경향을 보였지만, 농지경작을 위해 관개를 실시한 봄(3~4월)과 추수를 위해 물을 배수시켜 미꾸라지의 피부가 공기에 노출되었던 가을(8~9월)에 점액세포의 월별 변화율이 가장 크게 조사되었다. 또한 농지 수온이 급격하게 높았던 6월에 점액세포가 일시적으로 발달하는 모습이 관찰되었다. 계절에 따른 점액세포의 변화는 유동적인 농지환경에 대한 능동적 행동이자 피부호흡을 하기 위함으로 여겨진다.

• Clinical and Experimental Reproductive Medicine
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• 제47권1호
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• pp.68-76
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• 2020

Objective: Since sperm abnormalities are known to be a major reason for recurrent pregnancy loss (RPL), any defects in DNA structure and chromatin condensation can place embryos at risk in the early stage of development and implantation. As antioxidants such as vitamin C may play a protective role against the destruction of protamine genes in sperm chromatin, this study was conducted to evaluate the effects of vitamin C on chromatin and the expression of protamine genes in the male partners of couples with RPL. Methods: Twenty male partners of couples with RPL were selected as the intervention group and received vitamin C supplementation (250 mg daily for 3 months). Healthy fertile men (n = 20) were included as controls. Sperm chromatin, DNA integrity, and the expression levels of protamine genes were evaluated before and after treatment. Results: Significant differences were found in sperm morphology, protamine deficiency, and apoptosis between the two groups and before and after vitamin C administration. A significant change was found in mRNA levels of PRM1, PRM2, and the PRM1/PRM2 ratio after treatment. Conclusion: Daily oral administration of vitamin C may improve human sperm parameters and DNA integrity by increasing protamine gene expression levels in the male partners of couples with RPL. The beneficial effects of vitamin C supplementation as an antioxidant for the male partners of couples with RPL could lead to improved pregnancy outcomes in these cases.

• Journal of Ginseng Research
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• 제44권2호
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• pp.215-221
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• 2020

Background: Panax ginseng has been used for a variety of medical purposes in eastern countries for more than two thousand years. From the extensive experiences accumulated in its long medication use history and the substantial strong evidence in modern research studies, we know that ginseng has various pharmacological activities, such as antitumor, antidiabetic, antioxidant, and cardiovascular system-protective effects. The active chemical constituents of ginseng, ginsenosides, are rich in structural diversity and exhibit a wide range of biological activities. Methods: Ginsenoside constituents from P. ginseng flower buds were isolated and purified by various chromatographic methods, and their structures were identified by spectroscopic analysis and comparison with the reported data. The 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H- tetrazolium bromide method was used to test their cytotoxic effects on three human cancer cell lines. Results: Six ginsenosides, namely 6'-malonyl formyl ginsenoside F₁ (1), 3β-acetoxyl ginsenoside F₁ (2), ginsenoside Rh₂₄ (6), ginsenoside Rh₂₅ (7), 7β-hydroxyl ginsenoside Rd (8) and ginsenoside Rh₂₆ (10) were isolated and elucidated as new compounds, together with four known compounds (3-5 and 9). In addition, the cytotoxicity of these isolated compounds was shown as half inhibitory concentration values, a tentative structure-activity relationship was also discussed based on the results of our bioassay. Conclusion: The study of chemical constituents was useful for the quality control of P. ginseng flower buds. The study on antitumor activities showed that new Compound 1 exhibited moderate cytotoxic activities against HL-60, MGC80-3 and Hep-G2 with half inhibitory concentration values of 16.74, 29.51 and 20.48 μM, respectively.

• Molecules and Cells
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• 제27권2호
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• pp.159-166
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• 2009

Myocardial ischemia-reperfusion injury is a medical problem occurring as damage to the myocardium following blood flow restoration after a critical period of coronary occlusion. Oxygen free radicals (OFR) are implicated in reperfusion injury after myocardial ischemia. The antioxidant enzyme, Cu, Zn-superoxide dismutase (Cu, Zn-SOD, also called SOD1) is one of the major means by which cells counteract the deleterious effects of OFR after ischemia. Recently, we reported that a PEP-1-SOD1 fusion protein was efficiently delivered into cultured cells and isolated rat hearts with ischemia-reperfusion injury. In the present study, we investigated the protective effects of the PEP-1-SOD1 fusion protein after ischemic insult. Immunofluorescecnce analysis revealed that the expressed and purified PEP-1-SOD1 fusion protein injected into rat tail veins was efficiently transduced into the myocardium with its native protein structure intact. When injected into Sprague-Dawley rat tail veins, the PEP-1-SOD1 fusion protein significantly attenuated myocardial ischemia-reperfusion damage; characterized by improving cardiac function of the left ventricle, decreasing infarct size, reducing the level of malondialdehyde (MDA), decreasing the release of creatine kinase (CK) and lactate dehydrogenase (LDH), and relieving cardiomyocyte apoptosis. These results suggest that the biologically active intact forms of PEP-1-SOD1 fusion protein will provide an efficient strategy for therapeutic delivery in various diseases related to SOD1 or to OFR.

• 한국건축시공학회지
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• 제14권5호
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• pp.397-405
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• 2014

극한 염해환경에서 철근보강 지오폴리머 시험체의 외부전원법 전기방식 특성을 평가를 위하여 일련의 촉진실험을 실시하였다. 동시에 같은 조건의 보통 시멘트 콘크리트도 제조하여 비교 검토하였다. 환경조건은 침지대, 간만대, 그리고 크랙을 상정하였다. 지오폴리머는 밀실한 재료적 특성에 기인한 열화인자 침투 저항 증대에 의해 자연전위 뿐만 아니라 촉진 종료 후의 부식면적에서도 상당히 우수한 방식 성능이 있는 것으로 밝혀졌으며 향후 제작 양생 등의 문제를 개선함으로써 해양구조물로써의 활용이 다양해질 것으로 기대된다.