• Journal of the Korean Wood Science and Technology
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• 제48권4호
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• pp.527-547
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• 2020

어병 세균은 어류 양식업의 경제적 피해 뿐만 아니라, 인수공통감염원으로 알려진 전염성 병원균이다. 어병 세균을 제어하기 위해 지속적인 항생제의 사용은 부작용이 수반되기 때문에, 천연 유래 소재의 개발이 요구된다. 본 연구에서는 항생제대체제 개발을 위해 항세균효과가 우수한 침엽수 정유를 발굴하고자 하였다. 소나무과에 속하는 전나무 (Abies holophylla), 곰솔 (Pinus thunbergii), 섬잣나무 (Pinus parviflora), 솔송 (Tsuga sieboldii), 리기테다소나무 (Pinus rigitaeda)의 잎에서 hydro-distillation법을 이용하여 정유를 추출하였으며, 추출된 정유는 어병 세균인 Edwardsiella tarda, Photobacterium damselae, Streptococcus parauberis, Lactococcus garivieae에 대하여 항균력을 평가하였다. 그 결과, 전나무와 곰솔 잎 정유가 그람 음성 세균인 E. tarda와 P. damselae에 대하여 선택적으로 강한 항균력을 나타냈다. GC-MS 분석 결과, 전나무 잎 정유의 주요 성분은 (-)-bornyl acetate (29.45%), D-limonene (20.47%), camphene (11.73%)이고, 곰솔 잎 정유의 주요 성분은 α-pinene (59.81%)으로 각각 확인되었다. 또한, 미량으로 존재하지만 정유와 동일한 효능을 나타내는 유효 성분으로 oxygenated monoterpenes인 neryl acetate, (-)-borneol, (-)-carveol의 세가지 화합물을 구명하였다. 따라서 그람 음성어병세균의 생장억제효과가 우수한 전나무와 곰솔 잎 정유는 사료 첨가제, 수산용 의약품 등 생물학적 제제로 활용 될 수 있을 것으로 사료된다.

• Asia pacific journal of information systems
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• 제20권3호
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• pp.51-72
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• 2010

Given the extensive role of IS in everyday life and the increasing presence of women in IS users, understanding gender differences in individual technology continuance usage decisions is an important issue. Nevertheless, much of the large body of research on gender differences has just examined mean differences between women and men in terms of abilities, usage habit, and traits. Even though lots of psychology studies have shown that women, more than men, were influenced by affective factors, gender-affection-continuance use linkage has not been examined in the context of on-line shopping services. Therefore, the primary purpose of this paper is to seek to examine gender differences in terms of influence of affective factor in the context of IS continuance use. Meanwhile, IS continuance has been an important subject of study in the IT research area. To date, to explain why and how users are motivated to continue to use on-line shopping services, lots of theory-based research such as expectation-confirmation model (ECM) has been proposed. In particular, various affective factors have been proposed to explain continuance use of on-line shopping services recently. Affective factors have been regarded as essential factors for increasing relational strength and satisfaction. Several affective factors have been studied by prior IS adoption and continuance studies. Among them are enjoyment and anxiety. In IS continuance research, positive affect has been commonly and narrowly conceptualized and measured as the enjoyment which a person derives from using computers. Hence, in this study, we introduced intimacy factor, which was conceptually related to the quality of interactions and relationships in previous research. It also has been regarded as essential factors for strengthening human relationships. As a result, we have observed gender effect while examining intimacy-continuance bond. As expected based on the previous literatures, women seem to be more sensitive in affective factors. The contribution point here is that we find evidence in the context of on-line shopping services.

• 수산해양교육연구
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• 제27권5호
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• pp.1273-1289
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• 2015

The purpose of this study was to use the parent of the infant status and their media perception (3-7 five years) the infants' media use by examining the situation looking at the parents' use of media that cause impact on infants' media use parents will be validated accordingly to seek the solutions for the media and the involvement of infants perception. U City and 14 practitioners in preschool infants aged 5-7 target parents from 1307 people based in September 2014, a survey was conducted two months until October. This study was a mixed Methods for quantitative analysis of all the results and qualitative analysis of the results. Results for media use quantitative analysis of the results and impact parents have on infants' media use their media usage status of the parents and the media use of infants by their perceived status has been subjected to frequency analysis and hierarchical multiple regression analysis, parents perception results. Analysis of the solution for the immersion of the media and the infants unit of analysis was used for componential analysis. Through this study, parents would like to establish a plan to take advantage of essential educational content in the media and sought ways for the correct use of infants in the media and practice at home.

• 한국간호교육학회지
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• 제9권2호
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• pp.175-185
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• 2003

The purpose: This study was to describe the spiritual nursing care experiences of nursing students who were in a university, Seoul, Korea. Method: This study is based on descriptive analysis of case studies that were submitted by nursing students. Nursing students were 64 person who were sophomores in a university of the year 2000, 2001. Results: 1. The problems that students report for their subjects were: Loss of self-confidence, body image complex, health status problems, maladaptability, economic problems of home, guilty feeling, problems with dating, loneliness, uncertainty of their future, faith problem, accountability, stress and apart from intimate friends. 2. The methods which students use to solve the subjects's problems were: prayer with subjects, use the Scripture, conversation, meet frequently, listening, frequent phone call, explore problem solving methods together, write letters or E-mails, present with books or music CD etc. 3. After the students have experienced spiritual nursing care they feel that: satisfaction, lack of knowledge of spiritual care, understanding the importance of spiritual nursing care make a new resolution for others, understanding the importance of listening, understanding the power of prayer, the need of Bible study. Conclusion: Maintaining spiritual wellness is a important as maintaining physical fitness and essential for optimal well being. Therefore educating nursing students in developing and maintaining spiritual wellness is essential for the patient to achieve holism.

• 한국발생생물학회지:발생과생식
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• 제21권1호
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• pp.1-10
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• 2017

The use of human mesenchymal stem cells (hMSCs) in cell-based therapy has attracted extensive interest in the field of regenerative medicine, and it shows applications to numerous incurable diseases. hMSCs show several superior properties for therapeutic use compared to other types of stem cells. Different cell types are discussed in terms of their advantages and disadvantages, with focus on the characteristics of hMSCs. hMSCs can proliferate readily and produce differentiated cells that can substitute for the targeted affected tissue. To maximize the therapeutic effects of hMSCs, a substantial number of these cells are essential, requiring extensive ex vivo cell expansion. However, hMSCs have a limited lifespan in an in vitro culture condition. The senescence of hMSCs is a double-edged sword from the viewpoint of clinical applications. Although their limited cell proliferation potency protects them from malignant transformation after transplantation, senescence can alter various cell functions including proliferation, differentiation, and migration, that are essential for their therapeutic efficacy. Numerous trials to overcome the limited lifespan of mesenchymal stem cells are discussed.

• Asian-Australasian Journal of Animal Sciences
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• 제25권8호
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• pp.1138-1144
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• 2012

This study was conducted to evaluate the efficacy of the dipeptide form of phenylalanine as a new source of amino acid in terms of growth performance and whole-body amino acid composition in comparison to the free form for red seabream (Pagrus major). Fish ($1.46{\pm}0.001g$) were fed four isonitrogenous and isocaloric experimental diets containing 0.7 or 1.4% phenylalanine either in free or dipeptide form. A feeding trial was carried out in three replicates and the fish were fed to apparent satiation for six weeks. At the end of the feeding trial, feed intake of fish was influenced by both phenylalanine form and level and significantly higher values were obtained at an inclusion level of 0.7% and by the use of dipeptide form. However, the other growth parameters did not significantly differ among treatments. Whole-body amino acid compositions revealed no significant changes in concentrations of both essential and non-essential amino acids regardless of the increase in phenylalanine levels or the use of its different forms. The finding in this study indicates that juvenile red seabream can utilize dipeptide phenylalanine as efficiently as free form without any undesirable effects on growth performance or whole-body amino acid composition.

• The Plant Pathology Journal
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• 제28권4호
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• pp.446-452
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• 2012

The effect of heavy metals on seedling growth and pigment levels was studied in Arabidopsis using essential (Cu, Mn, and Zn) and non-essential metals (Pb and Hg). Generally increasing the concentrations of the metals resulted in a gradual decrease in root and shoot lengths, a decrease in chlorophylls, an increase in anthocyanins and a fluctuation in carotenoid content depending on the metal types. The toxicity of the metals decreased in the following order: Cu > Hg > Pb > Zn > Mn. Among the five metals, Cu was exceptionally toxic and the most potent inducer of anthocyanins. Pb induced the smallest quantity of anthocyanins but it was the strongest inducer of carotenoids. It suggests that the Cu-stressed Arabidopsis may use anthocyanins as its main antioxidants while the Pb-stressed Arabidopsis use carotenoids as its main protectants. All of the five metals induced an accumulation of anthocyanins. The consistent increase in anthocyanin content in the metal-stressed Arabidpsis indicates that anthocyanins play a major role in the protection against metal stresses.

• 한국수학교육학회지시리즈D:수학교육연구
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• 제18권3호
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• pp.171-185
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• 2014

Mathematically deductive reasoning skill is one of the major learning objectives stated in senior secondary curriculum (CDC & HKEAA, 2007, page 15). Ironically, student performance during routine assessments on geometric reasoning, such as proving geometric propositions and justifying geometric properties, is far below teacher expectations. One might argue that this is caused by teachers' lack of relevant subject content knowledge. However, recent research findings have revealed that teachers' knowledge of teaching (e.g., Ball et al., 2009) and their deductive reasoning skills also play a crucial role in student learning. Prior to a comprehensive investigation on teacher competency, we use a case study to investigate teachers' knowledge competency on how to teach their students to mathematically argue that, for example, two triangles are congruent. Deductive reasoning skill is essential to geometry. The initial findings indicate that both subject and pedagogical content knowledge are essential for effectively teaching this challenging topic. We conclude our study by suggesting a method that teachers can use to further improve their teaching effectiveness.

• 품질경영학회지
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• 제28권3호
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• pp.145-154
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• 2000

Effective management of knowledge is essential to keep up with demands of this challenging information age. The first step for this kind of management would be to define indicators to evaluate the quality of knowledge. In this paper, we use five latent variables (intrinsic quality, representational quality, ease of use of quality, maintainable quality, usage of quality) as basis for a preliminary path analysis for knowledge management. Preliminary study results showed that high intrinsic quality does not necessarily guarantee high frequency of use. A modified questionnaire is made and is used for SERVQUAL. The result of SERVQUAL shows that customers are not relatively happy about both intrinsic quality and its ease of use. Additional path analyses are done for both expected and observed quality indicators. The path model based on the expectation indicated that the presentation method of knowledge would induce its easy maintenance while that based on observation did not back up the same phenomenon.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1998년도 가을 학술발표회 논문집(I)
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• pp.121-126
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• 1998

Increased costs for cement have favoured the use of supplementary cementing materials in concrete. The use of fly ash in concrete has increased in the past few years. Concrete have been selected for use as a construction material in aggressive environment. The use of fly ash as concrete material has a role, and an understanding of its effect on concrete durability is essential to its correct and economical application. In this study, durability tests including permeability, freezing thawing resistance for Korean fly ash concrete are conducted. The durability characteristics of fly ash concrete are discussed.