• Biomolecules & Therapeutics
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• 제28권2호
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• pp.145-151
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• 2020

Alzheimer's disease (AD) is a devastating neurodegenerative disease and a major cause of dementia in elderly individuals worldwide. Increased deposition of insoluble amyloid β (Aβ) fibrils in the brain is thought be a key neuropathological hallmark of AD. Many recent studies show that natural products such as polyphenolic flavonoids inhibit the formation of insoluble Aβ fibrils and/or destabilize β-sheet-rich Aβ fibrils to form non-cytotoxic aggregates. In the present study, we explored the structure-activity relationship of naturally-occurring biflavonoids on Aβ amyloidogenesis utilizing an in vitro thioflavin T assay with Aβ1-42 peptide which is prone to aggregate more rapidly to fibrils than Aβ1-40 peptide. Among the biflavonoids we tested, we found amentoflavone revealed the most potent effects on inhibiting Aβ1-42 fibrillization (IC₅₀: 0.26 µM), as well as on disassembling preformed Aβ1-42 fibrils (EC₅₀: 0.59 µM). Our structure-activity relationship study suggests that the hydroxyl groups of biflavonoid compounds play an essential role in their molecular interaction with the dynamic process of Aβ1-42 fibrillization. Our atomic force microscopic imaging analysis demonstrates that amentoflavone directly disrupts the fibrillar structure of preformed Aβ1-42 fibrils, resulting in conversion of those fibrils to amorphous Aβ1-42 aggregates. These results indicate that amentoflavone affords the most potent anti-amyloidogenic effects on both inhibition of Aβ1-42 fibrillization and disaggregation of preformed mature Aβ1-42 fibrils.

• 한국어류학회지
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• 제22권4호
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• pp.249-255
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• 2010

빙어(Hypomesus nipponensis)의 육봉형과 소하성 개체군의 특성을 연구하기 위해 2008년 12월부터 2009년 4월까지 소양호와 향호에서 조사하였다. 육봉형인 소양호 개체군과 소하성인 향호 개체군에 있어 두 집단 간에 형태적 차이는 유사하였다. 산란시기는 육봉형인 소양호에서는 3월이었고 소하성 향호에서는 2월말이었다. 성적으로 성숙하여 생식이 가능한 크기는 전장이 60mm 이상되는 개체로 육봉형과 소하성 개체군에 있어서 동일하였다. 생식소 지수는 육봉형 집단(암컷 20.5%, 수컷 3.7%)이 소하성 집단(암컷 17.4%, 수컷 3.3%)에 비해 다소 높았다. 포란수는 육봉형 개체군(평균 4,902개)이 소하성 개체군(평균 7,325개)에 비해 매우 적었고 육봉형 개체군이 소하성 개체군에 비해 전장도 매우 작았었다. 소양호 개체군의 비만도는 평균 0.60(0.49~0.74)이었고 향호의 비만도는 0.70 (0.47~0.76)이었다. 먹이생물은 동물플랑크톤과 수서곤충이었으며 향호에 서식하는 개체군이 소양호 개체군에 비해 먹이의 크기가 큰 것을 주로 섭식하고 있었다.

• 한국양식학회지
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• 제20권3호
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• pp.154-159
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• 2007

Manchurian trout (Brachymystax lenok) is an endangered fish species in East Asia including the Korean peninsula. To establish a method for artificial propagation and to improve our understanding of the reproduction in the species, we have produced recombinant gonadotropins, follicle-stimulating hormone (r-mtFSH) and luteinizing hormone (r-mtLH), which may play central roles in reproductive activities. In the present study, the biological activities of the recombinant hormones were analyzed by gonadosomatic index (GSI), ovarian follicle diameter, and sex steroid levels in mature rainbow trout (Oncorhynchus mykiss). In the 6th day post-injection, FSH-injected fish were slightly decreased in the GSI value, although there were no significant differences among those of control, r-mtFSH, and r-mtLH treatments. Injection of the r-mtFSH increased follicle diameters significantly as compared with those of control- and r-mtLH-injected fish. The plasma steroid levels showed wide differences in the groups at 1, 3, or 6th day post-injection. Despite the variable steroid levels, three individuals receiving either r-mtFSH or r-mtLH showed a great increase in a maturation-inducing steroid, $17{\alpha},20{beta}$-dihydroxy-4-pregnen-3-one, at 3 and 6 days. Taken together, these results suggest that biological efficacies of the recombinant FSH and LH should be further studied in the Manchurian trout.

• ALGAE
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• 제24권4호
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• pp.249-256
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• 2009

The occurrence of Laminarionema elsbetiae (Ectocarpaceae, Phaeophyceae), as epi-endophyte of Rhodymenia pseudopalmata (Rhodymeniales, Rhodophyta), described from Santa Isabel, Rawson, Argentina. L. elsbetiae grows in the host tissues forming epi-endophytic relationship in the epidermal, cortical and medullar layers. Epiphytic thalli of L. elsbetiae were unbranched filaments emerging from hostis surface. Reproductive structures of L. elsbetiae on the host were absent. On the contrary, free cultured individuals formed different reproductive structures. Macrozoosporangia containing a single large motile zoospore originated from vegetative cells, they were conical to cylindrical in shape, 30-50 ${\mu}m$ in length and 18-20 ${\mu}m$ in wide. Uniseriate plurilocular zoosporangia were cylindrical shape, 40 ${\mu}m$ in length and 10-13 ${\mu}m$ in wide. Sexual fusion was not seen. In mixed cultures of L. elsbetiae with R. pseudopalmata fronds, L. elsbetiae infected the host, grew as in natural host and, formed macrosporangia between host subcortical cells. Gametophytes of L. elsbetiae were filaments with diffuse growth, branched with a branch pattern alternate or opposite. Gametangia were plurilocular, uni or biseriate and lateral. When mature they contained 2 to 6 isogametes. The presence L. elsbetiae on R. pseudopalmata could be defined as an epi-endophytic relationship. The percentage of infection of R. pseudopalmata thalli by L. elsbetiae was 34%.A25% of the infected thalli presented a low, non-symptomatic level infection, whereas a 62% and a 13% of them exhibited respectively moderate and high indexes of infection.

• 한국학교ㆍ지역보건교육학회지
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• 제10권2호
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• pp.69-83
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• 2009

Objectives: The purpose of this study was to analyze sexual permissiveness in order to solve the problems it creates for setting up desirable sexual culture. Methods: This study used Walker and Avant's methods for concept analysis. Results: Sexual permissiveness is the favorable attitude that is agreed upon and accepted as physiological, socio-cultural, and moral sexuality of an independent human who was born in man or woman. The property of sexual permissiveness that is accepted overall the humans are sex generously, change over the course of growth. sex consciousness, and attitudes toward sexual activity change based on race, age and religion etc. The values and beliefs of individuals that were formed in social and cultural background are bipolar. It is mutually agreed upon and accepted that volunarary activities should be spontaneous. The antecedents of sexual permissiveness included achievement of sexual development, establishment of the relationship, and mutual agreement between them. The consequences included mature relationship with others, meeting sexual needs, and raising sexual problems. Conclusions: These results suggest further studies are required that refine the diverse attributes of the concept of sexual permissiveness. The sexual education and enlightenment should be conducted at the period of secondary sex character.

• ALGAE
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• 제35권2호
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• pp.123-131
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• 2020

Sargassum macrocarpum is a rich source of anti-inflammatory compounds. Recently, one of the compounds, tuberatolide B, has been reported as a functional anti-inflammatory additive for foods and nutraceuticals. The artificial seeding, growth and maturation of S. macrocarpum were investigated from May 2018 to September 2019. Indoor culture experiments for induction of egg release were conducted at temperatures of 17, 20, 23, and 26℃ and irradiances of 0, 10, 20, 40, and 80 μmol photons m^-2 s^-1 under 14 : 10 h (L : D) photoperiod. Within a given treatment combination, higher temperatures and irradiance levels favoured the maturation of receptacles in S. macrocarpum. Using artificial temperature and irradiance control, thalli matured one month earlier than thalli in nature. Under natural condition, receptacle formation began in April, and the eggs were released in June and July. The release of eggs from the receptacles was promoted at 17-20℃ and 40-80 μmol photons m^-2 s^-1, and the fastest growth of germlings occuring at 15-17℃ and 40 μmol photons m^-2 s^-1. For mature thalli, 300 g wet-weight was sufficient to seed 100 m of seed string. Thalli grew to 10.5 ± 2.6 cm in length at a density of 6.7 ± 3.3 individuals m^-1 after 1 year of cultivation, from germination. This study demonstrates that it is possible to cultivate S. macrocarpum for the production of anti-inflammatory products.

• 한국산학기술학회논문지
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• 제21권3호
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• pp.180-189
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• 2020

본 연구는 대학생들이 수업에 대한 인식을 유형화하여 보다 효과적인 수업방식을 도입하는데 그 목적이 있다. 연구의 목적을 달성하기 위하여 Q 방법론을 활용하였으며, Q표본은 33개의 진술문으로 구성되었고, P표본은 교양수업을 듣는 40명의 학생으로 구성되었다. 연구결과 총 4가지의 유형이 도출되었으며 유형 1은 수업을 통하여 성장하려고 하는 욕구가 강한 '내실 있는 수업을 중요하게 생각하는 유형', 유형 2는 수업을 듣는 과정이 일을 할 때 실질적인 도움이 되기를 기대하는 '실무능력 향상을 중요하게 생각하는 유형', 유형 3은 수강인원수나 교수와의 소통, 실질적인 환경 등에 중점을 두는 '교육환경을 중요하게 생각하는 유형', 유형 4는 스스로 듣고 싶은 수업을 통하여 다양한 지적 역량을 향상시키고자 하는 '개인적인 역량 향상을 중요하게 생각하는 유형' 등으로 나타났다. 본 연구 결과가 대학 수업의 질을 향상하고 다양한 대학생의 수업 요구를 충족할 수 있도록 돕는 기초자료가 되기를 바란다.

• Fisheries and Aquatic Sciences
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• 제14권4호
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• pp.403-410
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• 2011

Scartelaos gigas is an amphibious mudskipper species that inhabits mud flats in Korea, China, and Taiwan. This fish is at risk of extinction because of its very restricted habitat and overexploitation. Information about this fish's reproductive characteristics is needed for species conservation. The sexual maturity and early life history of S. gigas were investigated through histological methods and direct observation of eggs in the wild, respectively. In total, 560 individuals of S. gigas were collected with the aid of fishermen from March 2003 to October 2003 at Jung-do Island, southwest Korea. Through microscopic observations of gonadal development, it was determined that S. gigas of both sexes were immature in April, but began to reach maturity in May, and were then fully mature by June, which was maintained until July. In August, some female fish developed early oocytes, but by September oocytes were observed to have degenerated and had been absorbed. Spawned eggs were elliptical and had an average size of 1.37 mm (long axis) by 0.69 mm (short axis). The newly hatched larvae (3.03 mm total length, TL) had an open mouth and anus, two melanophores near the anus, and one large melanophore between the 18th and 19th myomeres. The larvae (3.18 mm TL) showed absorption of the yolk and oil globule within 5 days after hatching and became prelarvae. This species should be considered vulnerable or conservation-dependent, and thus parental fish need to be protected from fishermen during the main spawning season (June).

• 한국치위생학회지
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• 제21권4호
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• pp.427-440
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• 2021

Objectives: We classified items required for dental hygienists' ethics training by domains. We administered a survey on experts using the Delphi method to collect opinions for guiding future trainings. Methods: 33 participants were selected and analyzed using the Delphi method thrice. Results: For relationships with patients, the item "1.3.1.1 I can keep the confidentiality of the information obtained from patients, including mature minors, related to their specific disease and treatment during medical care as well as other personal information of the patients." had the highest mean value (mean=4.88). For medical and social relations, "2.3.2.2 I can understand how staff provide dental services as a team and explain a dental hygienist's roles and responsibilities that enable a team to function effectively." had the highest mean value (mean=4.85). For individual specialized fields, "3.1.1.1 I can explain the roles and responsibilities in public health of individuals, the public, the state and professional dental hygienist." showed the highest mean value (mean=4.82). Conclusions: We identified 3 categories, 14 sub-categories, and 53 items on the scope of training and standards for ethical competencies for practical applications in professional ethics training of dental hygienists.

• 경영정보학연구
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• 제18권4호
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• pp.107-119
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• 2016

스마트 시대로 접어들면서 정보통신기술의 발달이 성숙기에 이르고 우리의 삶과 사회에 ICT가 미치는 영향이 점차 심화되고 있다. 이러한 맥락에서 경영정보학(MIS) 교수들이 중심이 된 국제정보시스템학회(Association of Information Systems: AIS)에서 2014년 12월에는 "ICT-enabled Bright Society Initiative(약칭 Bright ICT)"를 미래 비전 아젠다로 채택하였다. 본 연구에서는 Bright ICT Initiative에서 수행할 연구 아젠다 아이템들을 찾아내어 전략적 우선순위를 정하고 세부 프로그램을 논의하기 위한 기초 작업으로 brainstorming, clustering, ranking 의 단계를 거치는 델파이 스터디를 진행하였다. 연구 결과 11개의 주요 이슈를 발굴하였고 이어지는 설문조사를 통해 각 이슈들의 중요도 순위를 분석하였다. 나아가 각 이슈가 개인, 기업, 사회/국가에 미치는 영향의 중요도에 있어 연령과 성별에 따른 차이를 분석하였다.