• 제목/요약/키워드: interaction of small group

검색결과 206건 처리시간 0.023초

초등과학 영재교실에서 발견 학습 모형 수업에 효과적인 환경 조건의 탐색 (Effective Classroom Environments in Discovery Learning Classes for Gifted Science Pupils)

  • 이인호;전영석
    • 한국초등과학교육학회지:초등과학교육
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    • 제25권3호
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    • pp.307-317
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    • 2006
  • Those students with ability and interest in science should be supported to develop their potential and to reach high levels of achievement in science and technology. In order to ensure that gifted pupils are able to enhance their creativity as well as research abilities, appropriate learning programs and environments are essential. One of the various teaching and learning models for the gifted in science is the discovery learning model based on inductive science activities. There is a clear line of continuity between knowledge discovery at the forefront of research and student's learning activities. If students receive excellent training in organizing scientific concepts for themselves, they will be able to skillfully apply appropriate scientific concepts and solve problems when facing unfamiliar situations. It is very important to offer an appropriate learning environment to maximize the learning effect whilst, at the same time, understanding individual student's characteristics. In this study, the authors took great pains to research effective learning environments for gifted science students. Firstly, appropriate classroom learning environments thought by the teacher to offer the most potential were investigated. 3 different classes in which a revised teaching and learning environment was applied in sequence were examined. Inquiries were conducted into students' activities and achievement through observation, interviews, and examination of students' worksheets. A Science Education expert and 5 elementary school teachers specializing in gifted education also observed the class to examine the specific character of gifted science students. A number of suggestions in discovery learning classes for elementary students gifted in science are possible; 1) Readiness is essential in attitudes related to the inquiry. 2) The interaction between students should be developed. A permissive atmosphere is needed in small group activities. 3) Students require training in listening to others. In a whole class discussion, a permissive atmosphere needs to be restricted somewhat in order to promote full and inclusive discussion. 4) Students should have a chance to practice induction and abduction methods in solving problems.

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SV40 바이러스로 형질전환된 사람종양세포의 특성 (Proporties of SV4O-transformed Human Cells)

  • 최경희;홍승환
    • 한국동물학회지
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    • 제31권1호
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    • pp.49-55
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    • 1988
  • SV80와 같은 SV40로 형질전환된 사람세포는 종양을 일으킬 수 있는 능력을 가지고 있으나 면역기구인 흉선이 없는 누드마우스에서는 거부반응을 일으켜 종양을 일으키지 않는다. 그러나, 예외적으로 WI18/VA-2세포는 누드마우스에서 종양을 일으키며 이에서 얻는 두클론중 NW18C11은 종양을 일으키나 NW18C12는 종양을 일으키지 않는다. 본 실험에서는 이들 두 클론의 차이점들을 조사하였다. 실험결과, NW18C11은 NW18C12보다 더 많은수의 SV40 sequence를 포함하고 있음을 southern blot방법을 통해 확인하였으며 또한 immunofluoresce와 immunoprecipitation방법을 사용하여 두 클론 모두 정상크기의 SV40유전자산물인 large T와 small t 단백질을 생성함을 확인하였다. 한편 두 클론내에 포함되어 있는 바이러스유전자가 비형질전환새포로 하여금 생체내에서 악성종양 형성능력을 획득하도록 형질전환시킬수 있는지 확인하기 위해 두 클론의 DNA를 추출하여 마우스 NIH3T3세포에 주입시켜 형질전환된 세포를 선별하였다. 이 세포들은 모두 large T단백질을 생성하였으며 누드마우스에서 종양을 일으켰다. 이들 결과로써 NW18C12세포의 형질전환능은 완전하며, 이 세포가 누드마우스에서 거부반응에 기인하는 것으로 생각된다.

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중학교 "환경" 교과의 교수.학습 및 평가 방법 연구 (A Study on Teaching-Learning and Evaluation Methods of Environmental Studies in the Middle School)

  • 남상준
    • 한국환경교육학회지:환경교육
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    • 제7권1호
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    • pp.1-17
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    • 1994
  • This study was performed to determine appropriate teaching-learning and evaluation methods for Environmental Studies. To promote the relevance of our study to the needs of the schools and concerned educational communities of environmental education, we reviewed related literature, conducted questionnaire surveys, interviewed related teachers and administrator, held meetings with experts, and field-tested our findings. For selecting and developing teaching-learning methods of Environmental Studies, findings of educational research in general are considered. moreover, principles of environmental education, general aim of environmental education, orientations of environmental education, and developmental stages of middle school students in educational psychology were attended. In addition, relevance to the purpose of the Environmental Studies curriculum, appropriateness for value inquiry as well as knowledge inquiry, small group centered class organization, social interaction centered teaching-learning process, regional environmental situation, significance of personal environment, evaluation methods of Environmental Studies, multi- and inter-disciplinary contents of the Environmental Studies textbook, suitability to the evaluation methods of Environmental Studies, and emphasis on the social interaction in teaching-learning process were regarded. It was learned the Environmental Studies can be taught most effectively in via of holding discussion sessions, conducting actual investigation, doing experiment-practice, doing games and plate, role-playing and carrying out simulation activities, and doing inquiry. These teaching-learning methods were field-tested and proved appropriate methods for the subject. For selecting and developing evaluation method of Environmental Studies, such principles and characteristics of Environmental Studies as objective domains stated in the Environmental Studies curriculum, diversity of teaching-learning organization, were appreciated. We categorized nine evaluation methods: the teacher may conduct questionnaire surveys, testings, interviews, non-participatory observations; they may evaluate student's experiment-practice performances, reports preparation ability, ability to establish a research project, the teacher may ask the students to conduct a self-evaluation, or reciprocal evaluation. To maximize the effect of these methods, we further developed an application system. It considered three variables, that is, evaluates, evaluation objectives domains, and evaluation agent, and showed how to choose the most appropriate methods and, when necessary, how to combine uses of different methods depending on these variables. A sample evaluation instrument made on the basis of this application system was developed and tested in the classes. The system proved effective. Pilot applications of the teaching-learning methods and evaluation method were made simultaneously; and the results and their implications are as follows. Discussion program was applied in a lesson dealing with the problems of waste disposal, in which students showed active participation and creative thinking. The evaluation method used in this lesson was a multiple-choice written test for knowledge and skills. It was shown that this evaluation method and device are effective in helping students' revision of the lesson and in stimulating their creative interpretations and responces. Pupils showed great interests in the actual investigation program, and this programme was proved to be effective in enhancing students' participation. However, it was also turned out that there must be pre-arranged plans for the objects, contents and procedures of survey if this program is to effective. In this lesson, non-participatory observation methods were used with a focus on the attitudes of students. A scaled reported in general description rather than in grade. Experiment-practice programme was adopted in a lesson for purifying contaminated water and in this lesson, instruction objectives were properly established, the teaching-learning process was clearly specified and students were highly motivated. On the other hand, however, it was difficult to control the class when some groups of students require more times to complete their experiment, and sometimes different results. As regards to evaluation, performance observation test were used for assessing skills and attitudes. If teachers use well-prepared Likert scale, evaluation of all groups within a reasonablely short period of time will be possible. The most effective and successful programme in therms of students' participation and enjoyment, was the 'ah-nah-bah-dah-market' program, which is kind of game of the flea market. For better organized program of this kind, however, are essential, In this program, students appraise their own attitudes and behavior by responding to a written questionnaire. In addition, students were asked to record any anecdotes relating to self-appraisal of changes on one's own attitudes and behaviours. Even after the lesson, students keep recording those changes on letters to herself. Role-playing and simulation game programme was applied to a case of 'NIMBY', in which students should decide where to located a refuse dumping ground. For this kind of programme to e successful, concepts and words used in the script should be appropriate for students' intellectual levels, and students should by adequately introduced into the objective and the procedures of the lessons. Written questionnaire was used to assess individual students' attitudes after the lesson, but in order to acquire information on the changes of students' attitudes and skills, pre-test may have to be made. Doing inquiry programme, in which advantages in which students actually investigated the environmental influence of the areas where school os located, had advantages in developing students' ability to study the environmental problems and to present the results of their studies. For this programme to be more efficient, areas of investigation should be clearly divided and alloted to each group so that repetition or overlap in areas of study and presentation be avoided, and complementary wok between groups bee enhanced. In this programme, teacher assessed students' knowledge and attitudes on the basis of reports prepared by each group. However, there were found some difficults in assessing students' attitudes and behaviours solely on the grounds of written report. Perhaps, using a scaled checklist assessing students' attitudes while their presentation could help to relieve the difficulties.

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1977~2013년 한국의류학회지와 해외 의류학 저널 출판논문의 연구동향 및 저자, 연구관계망 분석 -피복과학 분과를 중심으로- (Network Analysis and Trends of Articles in the Journal of the Korean Society of Clothing and Textiles and International Journals (1977-2013) -Clothing Science Related-)

  • 박성진;하정윤;이혜은;이주영
    • 한국의류학회지
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    • 제38권6호
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    • pp.834-844
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    • 2014
  • This study investigated original articles published in the Journal of the Korean Society of Clothing and Textiles (JKSCT) from 1977 through 2013 with a consideration of the research collaboration structure. Two international journals were chosen: Textile Research Journal (TRJ) and International Journal of Clothing Science and Technology (IJCT) in order to compare the clothing science research trends of JKSCT-publications to international trends. The collected data from the three journals were used to probe periodic changes in the number of publications and nationality of authors to find the relative international position of Korean clothing and textile researchers. Figures, tables, and references in each article were counted to suggest the most suitable way to express and interpret clothing science results. In addition to the quantified data analysis, a qualified analysis was investigated with the co-author network analysis. The findings revealed an increase in the number of published articles in JKSCT until 2009 with the rapid decrease after. The number of co-authors in JKSCT was relatively small compared to TRJ and IJCT but growing in the clothing and textile science group. The number of references in JKSCT increased 3 times from 1977 to 2013; therefore, it was assumed there is more recent active clothing and textile research. Lastly, a pattern of authors' interaction and the most contributed authors in the network was illustrated in the clothing and textile science group. The present study confirms that JKSCT has made significant progress toward knowledge development in the clothing and textile field and suggests that the analysis of accumulative knowledge helps researchers broaden the scale and approach of studies.

초등학교 아동의 성역할 정체감 및 가정환경변인에 따른 의복행동연구 (A Study on the Clothing Behavior of Elementary School Students in Connection with Sex-Role Identity and Home Enviornments)

  • 전경란
    • 한국생활과학회지
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    • 제6권2호
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    • pp.133-144
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    • 1997
  • Clothing is considered as a means of self-projection in the childhood and children show clear preference on their own favorite clothing on which their latent identity is reflected. Changing sex-role identity, in particular, in the modern complex society specially affects the clothing behavior of children. The purpose of this study is to investigate the clothing behavior of children in conjunction with sen-role identity and home environment variables. This study will provide fundamental information on the clothing behavior in the childhood and be of help in selecting appropriate clothing in accordance with the variation of sex-role identity. Necessary information for this study was obtained through a questionaire. 'Bem sex-role identity inventory' was used to investigate the effect of sex-role identity and the clothing behavior was studied in conjunction with the factors of conformity, dependence, aesthetics and interest. The subjects of investigation are composed of three hundred male and female elementary school students in the 5th and 6th grades. For the statistical analysis of the collected data, percentage(%), mean value(M), standard deviation(SD) and Pearson's correlation coefficient were calculated and t-test, $x^2$-test, and Duncan's multiple range test were performed. The results form this study are as follows : 1. Sex-role identity shows a little difference according to gender, order of a birth and standard of living. This small difference is shown to be statistically insignificant. 2. In clothing behavior in connection with the sex-role identity, statistically significant trend was not found in typical sex-role identity group. However, clothing behavior in modernistic sex-role identity group exhibits statistically significant results in the factors of dependence, aesthetics and interest at the level of P<.001. 3. As concerns the clothing behavior in connection with gender, boy students show statistically more significant tendency in aesthetics and interest than girls do. However, boy students show statistically more significant tendency in aesthetics than girls do in connection with the standard of living. Although the clothing behavior associated with the level of parents education, mother's age and existence of mother's job shows a little difference in mean values, statistically significant trend was not detected. 4. Clothing behavior of the children shows a meaningful correlation between the factors. 5. Through 3-dimensional variables analysis, it is found that there is no mutual interaction between gender, sex-role identity and standard of living on the clothing behavior. The results from MCA supplementary analysis reveal that there is difference according to the gender, sex-role identity and standard of living.

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Effects of Chromium Yeast on Performance, Insulin Activity, and Lipid Metabolism in Lambs Fed Different Dietary Protein Levels

  • Yan, Xiaogang;Zhang, Wei;Cheng, Jianbo;Wang, Runlian;Kleemann, David O.;Zhu, Xiaoping;Jia, Zhihai
    • Asian-Australasian Journal of Animal Sciences
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    • 제21권6호
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    • pp.853-860
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    • 2008
  • This experiment was conducted to study the effects of chromium (Cr), dietary crude protein (CP) level and potential interactions between these two factors on growth rate and carcass response, insulin activity and lipid metabolism in lambs. Forty-eight, 9-week-old weaned lambs (Dorper$\times$Small-tail Han sheep, mean initial body weight = $22.96kg{\pm}2.60kg$) were used in a $2{\times}3$ factorial arrangement of supplemental Cr (0 ppb, Cr0; 400 ppb, Cr1; or 800 ppb, Cr2 from chromium yeast) and CP levels (157 g/d to 171 g/d for each animal, LP; or 189 g/d to 209 g/d for each animal, HP). Growth data and blood samples were collected at the beginning and end of the feed trial, after which the lambs were killed. Both Cr additive groups and the HP group increased final weight and average daily gain, especially the Cr1 and HP group (p<0.01). HP increased pelvic fat weight (p<0.05), fat thickness of the 10th rib (p<0.05), longissimus muscle area (p<0.01) and rate of deposition of intramuscular fat (p<0.01). Supplemental Cr decreased the rate of deposition of intramuscular fat (p<0.05). Fasting insulin level and the ratio of insulin to glucose were lower with Cr1 than other groups, but with no significant difference. Glucose concentration was not affected by any treatment. Nonesterified fatty acids increased in the Cr1 (p<0.05) and HP (p<0.05) conditions and there was a significant $Cr{\times}CP$ interaction (p<0.05). Cr1 decreased triglycerides (p<0.05) and total cholesterol (p = 0.151) and HP increased high-density lipoprotein cholesterol (p<0.05). Cr1 decreased lipoprotein lipase activity in subcutaneous adipose tissue (aLPL, p<0.05) and the ratio of aLPL to lipoprotein lipase activity in skeletal muscle (mLPL, p = 0.079). mLPL and hepatic lipase (hHL) were not affected by any treatment. In the present study, Cr had limited effects on growth rate and carcass response, whereas Cr and CP had some notable effects on plasma metabolites and enzyme activities. Cr has a potential effect on energy modulation between lipid and muscle tissue. In addition, few $Cr{\times}CP$ interactions were observed.

말뚝식과 블록식이 혼합된 시멘트혼합처리공법(DCM)의 구조체 해석 비교 연구 (A Comparative Study of Structural Analysis on DCM Improved by Pile and Block Type)

  • 신현영;김병일;김경오;한상재
    • 한국지반공학회논문집
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    • 제30권4호
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    • pp.5-19
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    • 2014
  • 본 논문에서는 천층블록/심층말뚝 혼합식 시멘트혼합처리 공법을 구조체적 관점에서 해석하였고, 각 방법별 특징 및 관련 거동을 분석하였다. 연속보 해석법의 경우 침하량을 매우 작게 예측하였고, 천층블록의 전단력과 휨응력은 다소 크게 예측하였다. Frame 해석법의 경우 천층블록의 부재력과 장주의 부재력은 수치해석법과 가장 근접한 거동을 예측하였지만, 장주의 침하는 작게 예측하여, 장주 반력을 이용한 별도 침하계산을 실시해야하는 것으로 나타났다. 지반아칭법과 말뚝지지전면기초해석법의 경우 장주의 하중분담율이 타방법에 비해 매우 커서 장주의 축력이 과대 예측되었다. 천층블록/심층말뚝 혼합식 시멘트혼합처리공법을 적용하면, 천층블록의 침하 및 지반반력은 중앙에서 가장 크고, 외곽에서 가장 작았다. 또한, 개량체와 지반간의 상호작용을 고려할 수 있는 해석법에서 장주 개량체가 분담하는 하중은 약 20~45% 범위를 보였고, 응력분담비는 일반적인 말뚝식 DCM 공법보다 작은 약 2.0~5.0정도의 범위를 나타내었다. 장주 두부 경계조건에 따라 최대 부재력에서는 유사하지만, 두부 구속조건에서는 장주의 위치에 따라 축력 및 연직변위는 서로 다르게 나타났다.

초등학교 수학 수업에서의 구체물 활용과 수학적 의사소통에 관한 연구 - 2학년 아동을 중심으로 - (A Study of Using Concrete Materials and Mathematical Communications in the Primary Mathematics Class - Focused on 2nd Grades in Primary school -)

  • 이미애;김수환
    • 한국초등수학교육학회지
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    • 제5권1호
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    • pp.99-120
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    • 2001
  • 본 연구는 초등학교 저학년 아동의 수학적 의사소통 지도의 방향을 모색하고 의사소통에 대한 구체물 활용의 효과에 대하여 새로운 방향을 제시하는데 목적을 두고 수학적 의사소통에는 어떠한 특성이 있으며, 구체물이 수학적 의사소통에 어떠한 영향을 미치는지, 수학 학습에 구체물이 어떠한 영향을 미치는지 알아보고자 하였다. 의사소통 특성으로는 수학적 기호나 용어가 익숙하지 못하고 대체 용어를 사용하고 생활 속의 경험을 학습에 잘 적용시키며, 소수 아동들이 수업을 주도하며, 소집단에서 이루어지는 대화의 방향이 과제 해결 중심으로 이루어지지 못하고 있다. 구체물은 말하기 활동을 촉진시키며, 오류를 쉽게 확인하게 하며 추측과 예상 활동을 수월하게 하고 소집단 활동이 활발히 이루어지게 한다. 반면에 구체물을 활용하면서 교사에게 집중하지 않고 이탈행동을 보임으로써 듣기 활동이 제대로 이루어지지 않고 있다. 학습에 주는 영향으로는 참여도를 높이고, 부진아 학습을 돕고, 개념 형성에 도움을 준다. 또한 과제 해결 능력에 따라 수준별 학습이 쉽게 이루어지도록 한다. 그러나 구체물에 따라 학습에 활용 정도가 다르게 나타났으며 아동들은 절차적 지식보다 개념적 지식을 더 중시하고 있었다. 따라서 구체물은 수학 수업에서 의사소통을 활발하게 이루어지게 도와주며 수학 학습에도 많은 영향을 미치게 되므로 저학년의 수학 수업에서는 구체물의 활용이 꼭 필요하다. 또한 교사는 이러한 아동들의 의사소통의 특성을 고려하여 의사소통 활동이 활발히 이루어질 수 있는 교수 학습 방법을 모색해야할 것이다.된다0.9 mg/ml의 수준에서 측정되었고, 제 11세대에서는 유즙내 인간 hIL-10의 발현 수준을 분석하였을 때, 그 농도는 평균 5.7± 1.5 mg/ml의 수준에서 측정되었고, 제 12세대에서는 유즙내 인간 hIL-10의 발현 수준을 분석하였을 때, 그 농도는 평균 6.3±3.5 mg/ml의 수준으로 측정되었고, 제 13세대에서는 유즙내 인간 hIL-10의 발현 수준을 분석하였을 때, 그 농도는 평균 6.8±4.5 mg/ml의 수준으로 측정되었고, 제 14세대에서는 유즙내 인간 hIL-10의 발현 수준을 분석하였을 때, 그 농도는 평균 6.8±3.1 mg/ml의 수준으로 측정되었다. 이러한 수준은 제 1 세대의 것보다 높은 결과로 형질전환 생쥐에서 인간 IL-10 유전자의 발현은 최소한 15 세대까지 지속적으로 유지된다는 것을 알 수 있었으며, 장기 세대까지도 발현수준이 유지될 것으로 판단된다. 이러한 연구결과는 계통으로 확립된 형질전환 동물에 부여된 새로운 유전형질은 지속적으로 후대로 유전될 수 있음을 제시한다.

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Poxvirus 감염(感染)에 있어서의 Virus-숙주세포(宿主細胞)의 상호관계(相互關係) 1. Cowpox Virus-FL 세포계(細胞系)의 세포화학적(細胞化學的) Autoradiography 및 세포면역학적해석(細胞免疫學的解析) (Studies on Host-Virus Interaction of Poxviruses 1. Cytochemical, Autoradiographic and Immunocytological Analysis in Cowpox Virus-FL Cell System)

  • 김우호
    • 대한수의학회지
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    • 제15권1호
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    • pp.57-67
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    • 1975
  • The poxvirus group is considered to be a typical cytoplasmic inclusion forming virus. Every poxvirus has been reported to produce only one kind of inclusion in the infected tissues. A vague concept that inclusions of poxviruses are eosinophilic or acidophilic has prevailed. Although many papers and theories about the nature of the inclusion have been presented, most of them are not quite convincing on the point of the relations with virus multiplication, and an analysis of papers published showed that there seem to be many discrepancies in the descriptions of the nature of the poxvirus inclusions. Comparative studies on host-virus interaction with cowpox, orf, swinepox and fowlpox viruses which selected from each Group (I-IV) of poxviruses were performed from the morphological and virological standpoints. At first, in cowpox virus-FL cell system, as a comparative model, cytoplasmic inclusion, nucleic acid metabolism by autoradiography and detection of viral antigen by immunofluorescence were studied and obtained the results as follows: 1. The focus-like cytopathic effect (CPE) at early stage developed to entire culture at terminal stage of infection, and also the developing status of CPE was correlated to viral doses for inoculation. Two kinds of cytoplasmic inclusions which named A and B type were easily observed by Giemsa, hematoxylin-eosin (H & E) and May-Greenwald Giemsa (MGG) stainings in the infected cells. The B type inclusions were formed at early stage of infection and the A type inclusions were produced subsequently the B type formation. The B type which common type inclusion in poxviruses was a small compact or aggregate at early stage and developed to a large diffuse body at terminal stage of infection. On the other hand, the A type inclusion which depend upon the kind of virus was appeared as round and discrete shape, and its size and number was increased gradually during the culture period. It was characteristic to form distinct halos around the both types of inclusions in acid fixed, H & E stained preparations of infected cultures. The B type inclusion was always positive in Feulgen reaction and showed as DNA containing body but the A type inclusion was not. 2. In the relationship between inclusion and DNA metabolism of infected cells by the qualitative autoradiography using 3H-thymidine, the appearance of silver grains was coincided with B type inclusion but not with A type inclusion. This showed that the DNA synthesis was proceeded in all B type inclusions except those in the terminal stage with a diffuse form. This suggested that the B type inclusions are only sites of DNA synthesis and this was proceeded after the cell infection independently. The activity of DNA synthesis of the inclusions was nearly the same as that of the nucleic of normal cells and non-inclusion bearing cells. and non-inclusion bearing cells. Regardless of the size of the degree of DNA synthesis of the B type inclusion, inclusion bearing cells all showed remarkable suppression of nuclear DNA synthesis. 3. By the direct fluorescent antibody technique viral antigen in infected cells was detected. The B type inclusions have been proved to contain a great deal of viral antigen, whereas the basic substance of A type inclusion did not show antigenicity except the round edge. It was suggested that the round edge fluorescence might be caused by the glare of cytoplasmic viral antigen which pushed out and concentrated by the A type inclusion development. 4. Hemorrhagic red pock formations on chorioallantoic membrane of embryonated chicken egg had proved the characteristic of used viral strain. 5. By the above studies on the nature of two types of inclusions and the role they play in virus multiplication, it was concluded that the B type inclusion must be the site of the synthesis of viral DNA and protein as well as the site of the virus.

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새로운 포단드에 의한 피크린산 일가 양이온 염의 용매추출 (The Solvent Extraction of Univalent Cation Picrates by New Podands)

  • 정종화;조성배;김진은;김재상;이심성
    • 분석과학
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    • 제6권1호
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    • pp.29-37
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    • 1993
  • 말단기에 페닐(B), 벤질(Bz), 피리딘(Py), 퀴놀린(Q) 또는 나프탈렌(Np), 그리고 에테르 사슬에 산소(O) 또는 황(S) 주개원자를 갖는 몇 가지 포단드를 합성하여 1가 양이온과의 결합특성을 NMR 적정법과 용매추출법으로 조사하였다. NMR 적정에 의하면 대부분의 포단드는 1가 양이온과 1:1 착물을 형성하며, 특히 은이온과의 상호작용에서 에테르 사슬의 황 원자는 안정도를 증가시키는 효과를 나타내었다. 또한 포단드를 이용하여 에테르 수용액층에서 클로로포름층으로 알칼리 금속, 은, 탈륨 및 암모늄 등의 피크린산 1가 양이온염을 추출하였다. 은이온에 대한 추출률은 $Q_2O_4$, $Q_2O_5$$BQO_5$와 같이 퀴놀린을 포함하는 포단드의 경우 각각 86.8, 86.6 및 48.0%였으나 나프탈렌을 갖는 $Np_2O_4$$Np_2O_5$에 의해서는 거의 추출되지 않았다. 한편, $Bz_2O_3S_2$(89.4%), $B_2O_2S_2$(76.8%), $B_2O_3S_2$(58.9%), $Py_2O_2S_2$(58.8%), $Py_2O_3S_2$(42.1%) 및 $B_2O_4S$(15.0%)의 경우, 황 원자와 벤질기를 갖는 $Bz_2O_3S_2$가 가장 큰 은이온 추출 선택성을 나타내었다. 이러한 결과는 HSAB 이론에 의한 황 원자와 은이온과의 강한 상호작용 뿐 아니라 페닐기 대신에 벤질기가 치환됨으로써 유연한 메틸렌기 공간에 의해 두 방향족 말단기 사이의 ${\pi}-{\pi}$ 스택킹 상호작용이 효과적으로 증가하기 때문이다. 추출계수는 안정도 및 추출률과 비슷한 경향성을 나타내었는데, 이로부터 추출계수에 주된 영향을 미치는 요인으로는 포단드의 구조와 밀접한 관계가 있는 안정도임을 알 수 있었다.

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