• Title/Summary/Keyword: selection function

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Analyzing the Characteristics of Pre-service Elementary School Teachers' Modeling and Epistemic Criteria with the Blackbox Simulation Program (블랙박스 시뮬레이션에 참여한 초등예비교사의 모형 구성의 특징과 인식적 기준)

  • Park, Jeongwoo;Lee, Sun-Kyung;Shim, Han Su;Lee, Gyeong-Geon;Shin, Myeong-Kyeong
    • Journal of The Korean Association For Science Education
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    • v.38 no.3
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    • pp.305-317
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    • 2018
  • In this study, we investigated the characteristics of participant students' modeling with the blackbox simulation program and epistemic criteria. For this research, we developed a blackbox simulation program, which is an ill-structured problem situation reflecting the scientific practice. This simulation program is applied in the activities. 23 groups, 89 second year students of an education college participated in this activity. They visualized, modeled, modified, and evaluated their thoughts on internal structure in the blackbox. All of students' activities were recorded and analyzed. As a result, the students' models in blackbox activities were categorized into four types considering their form and function. Model evaluation occurred in group model selection. Epistemic criteria such as empirical coherence, comprehensiveness, analogy, simplicity, and implementation were adapted in model evaluation. The educational implications discussed above are as follows: First, the blackbox simulation activities in which the students participated in this study have educational implications in that they provide a context in which the nature of scientific practice can be experienced explicitly and implicitly by constructing and testing models. Second, from the beginning of the activity, epistemic criteria such as empirical coherence, comprehensiveness, analogy, simplicity, and implementation were not strictly adapted and dynamically flexibly adapted according to the context. Third, the study of epistemic criteria in various contexts as well as in the context of this study will broaden the horizon of understanding the nature of scientific practice. Simulation activity, which is the context of this study, can lead to research related to computational thinking that will be more important in future society. We expect to be able to lead more discussions by furthering this study by elaborating and systematizing its context and method.

A study on sagittal root position of maxillary anterior teeth in Korean (한국인에서 상악 전치의 시상 치근 위치에 대한 연구)

  • Kong, Hyun-Jun
    • Journal of Dental Rehabilitation and Applied Science
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    • v.36 no.2
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    • pp.88-94
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    • 2020
  • Purpose: The purpose of this study was to analyze the sagittal root position of maxillary anterior teeth and report the frequency of each classification in Korean for immediate implant placement. Materials and Methods: A retrospective review of cone-beam computed tomography (cone-beam CT) images was conducted on 120 patients (60 male and 60 female) who fulfilled the inclusion criteria. After reorientation of the axis, cone-beam CT images were evaluated and the relationship of the sagittal root position (SRP) of the maxillary anterior teeth to its associated osseous housing was recorded. Class I, II, and III were classified respectively when the root was positioned on the labial, central, and palatal aspect of the alveolar bone. Class IV was the position that at least two thirds of the root is engaging both the labial and palatal cortical plates. Then, the angulation of the root axis and the alveolar bone axis was measured. Descriptive statistics and Kruskal-Wallis test were used to compare the angulation according to the root position and SRP class. Results: The frequency distribution of sagittal root position of maxillary anterior teeth indicated that 81.1%, 10.3%, 1.9%, and 6.7% were classified as Class I, II, III, and IV, respectively. The sagittal angulation at approximately 77.5% of central incisor, lateral incisor, and canine was < 20 degrees, but the angle at more than 42.7% of canine was ≥ 20 degrees. Within the class, the angulation was statistically significantly greater in Class I (16.19) compared to Class II (8.72) and Class III (9.93), and smaller in Class IV (3.79). Conclusion: Within the limitation of this study, a majority of the maxillary anterior roots were positioned close to the buccal cortical plate. However, some roots have very thin alveolar bone and sagittal angulation larger than 30 degrees. Therefore, cone-beam CT analyses of the sagittal root position and the sagittal angulation are recommended for the selection of the appropriate dental implant treatment approach.

Current status of Brassica A genome analysis (Brassica A genome의 최근 연구 동향)

  • Choi, Su-Ryun;Kwon, Soo-Jin
    • Journal of Plant Biotechnology
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    • v.39 no.1
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    • pp.33-48
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    • 2012
  • As a scientific curiosity to understand the structure and the function of crops and experimental efforts to apply it to plant breeding, genetic maps have been constructed in various crops. Especially, in the case of Brassica crop, genetic mapping has been accelerated since genetic information of model plant $Arabidopsis$ was available. As a result, the whole $B.$ $rapa$ genome (A genome) sequencing has recently been done. The genome sequences offer opportunities to develop molecular markers for genetic analysis in $Brassica$ crops. RFLP markers are widely used as the basis for genetic map construction, but detection system is inefficiency. The technical efficiency and analysis speed of the PCR-based markers become more preferable for many form of $Brassica$ genome study. The massive sequence informative markers such as SSR, SNP and InDels are also available to increase the density of markers for high-resolution genetic analysis. The high density maps are invaluable resources for QTLs analysis, marker assisted selection (MAS), map-based cloning and comparative analysis within $Brassica$ as well as related crop species. Additionally, the advents of new technology, next-generation technique, have served as a momentum for molecular breeding. Here we summarize genetic and genomic resources and suggest their applications for the molecular breeding in $Brassica$ crop.

The costume culture of China is as old and varied as her long history (중국 소수민족의 복식 연구(1))

  • 박춘순
    • Journal of the Korean Society of Costume
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    • v.26
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    • pp.175-206
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    • 1995
  • The costume culture of China is as old and varied as her long history. As China is a multiracial nation and consists of fifty-six min-ority races including Han race, there are not only fifty-six different costumes in China but each races' costume habit is very different. Therefore, Chinese penninsula can be considered an enor-mous exhibition center of the costumes. This study undertook on the assumption that the costumes' mainstream of Korea and east-northern Asia as well as that of China could be examined by investigating the minority races' costumes in the east-and west-northern areas of China. The process of evolution of the costume of a particular people, country or area is subject not only to constraints related to geography such as climate, topography or local products but is also affected by numorous environmental influences including cultural, economic, social and even pol-itical ones in terms of the selection of material, styling, color and standard of tailoring. In other words, things like philosophy of life, religious be-lief, aesthetic outlook, moral code, class system, degree of affluence, and cultural exchange will all be reflected directly or indirectly by features of a people's or country's style costume. Of course, there are several factors affecting to the style of costume of the minority people in China. However, the only three factors-geo-graphical and environmental, production method, and religious belef-will be touched in this study. First of all, the geograghical and eenviron-mental factor would be the decisive one because the costume should be designed to overcome the constraints of climate and geographical environ-ments. Accordingly, each race has an unique style of costume. The costume of the minority races in the northern parts are loose and wide, and made of warm furs. For instance, Mongolian robe has the quality of anti-wind, anti-cold and warmness, and the width of a sleeve is narrow and long. Secondly, the costume style can be said to be limited by the production pattern, when the geo-graphical environment was affected to decide the costume style, the production pattern was together affected to it . In case of Mongolian robe, they should satisfy the dual condition as the practical function. One is the condition that they should be fitted to the climate, and the other is the condition that they should be suit-able to the nomadic life. Mongolian robes are suitable to the nomadic peoples because they are designed for not only overcoming the cold wind and weather but being used as the bedquit at night. The costumes of Hoche people was made of the skin of the fish and wild animals because of their main means of living being fishing and hunting. Accordingly, their costumes are dur-able, warm and water-proof. Finally, the style of the costume is affected by the religious belief. In other words, the pattern in fashion is closely related with the religious be-lief or ancestor worship and nature worship. Ac-cordingly, the symbols of these worship are often emerged in the decoration of the costume. The design of costume of the people in the northern areas of China is very simple. It is related with their monotheism. On the other hand, the costumes of twen쇼 minority races in the east-northern parts of China can be devided into three racial groups such as the long robes of Man people and Mongols, Tunics of the peoples in the west-northern areas, and the pants and jackets of Hoche people. The minorority races all has not only the unique costume habit but their costumes are also related with their living style and production means.

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A Study on Hepatomegaly and Facial Telangiectasia in a Group of the Insured (간종대(肝腫大)와 안면모세혈관확장(顔面毛細血管擴張)의 보험의학적연구(保險醫學的硏究))

  • Im, Young-Hoon
    • The Journal of the Korean life insurance medical association
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    • v.4 no.1
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    • pp.110-132
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    • 1987
  • A study on hepatomegaly detected by abdominal palpation, and facial telangiectasia in a total of 3,418 insured persons medically examined at the Honam Medical Room of Dong Bang Life Insurance Company Ltd. from February, 1984 to August, 1985 was undertaken. The results were as follows: 1) Hepatomegaly was found in 383 cases(27.5%) among the 1,395 insureds of male and in 163 cases(8.1%) among the 2,023 insureds of female. The difference of incidence of hepatomegaly between all males and females showed statistical significance(p<0.001). In each age group, the incidence of hepatomegaly in :nale was higher than that in female. The incidence of hepatomegaly in each age group in male increased cnosiderably with age; it showed 11.6%,16.2%, 42.6% and 52.9% from second to sixth decade in order, thereafter in seventh decade it decreased to 26.7%, While the incidence of hepatomegaly in female increased slightly in each age group. 2) Facial telangiectasia was found in 318 cases(22.8%) among all males and in 157 cases(7.8%) among all females. The difference of incidence of telangiectasia between all males and females showed statistical significance(p<0.001). In each age group, the incidence of telangiectasia in male was higher than that in female, except of second decade. The incidence of facial telangiectasia in each age group in male increased considerably with age; while it increased slightly in female. 3) Facial telangiectasia accompanied by hepatomegaly was found in 235 cases(61.4%) among 383 cases of hepatomegaly in male and in 69 cases(42.3%) among 163 cases of hepatomegaly in female. The difference of incidence of telangiectasia between males and females show ed statistical significance(p<0.001). 4) Facial telangiectasia without spider angiomata accompanied by hepatomegaly was found in 201 cases(52.5%) among 383 cases of hepatomegaly in all males and in 67 casgs(41.4%) among 163 cases of hepatomegaly in all females; facial spider angiomata accompanied by hepatomegaly was found in 34 cases(8.9%) among 383 cases of hepatomegaly in all males and in 2 cases(1.2%) among 163 cases of hepatomegaly in all females. 5) Abnormal SGOT activity was found in 19 cases(7.9%) among 242 cases of hepatomegaly in all males and in one case(1.5%) among 67 cases of hepatomegaly in all females. The difference of incidence of abnormal SGOT activity showed statistical significance(p<0.001). The incidence of abnormal SGOT activity by the size of hepatomegaly, that is, palpated <1 finger's breadth, <2 fingers' breadth and ${\geqq}2$ fingers' breadth, revealed 2.2%, 6.0% and 60.0% respectively in all males, while abnormal SGOT activity was found only one case in fifth decade among 67 cases of hepatomegaly in all females. 6) In ordinary medical examination(the insured amount is low) abnormal SGOT activity was found in 7 cases(4.8%) among 146 cases of hepatomegaly palpated $1\frac{1}{2}$ fingers' breadth and under, while it was not found in 37 cases of the same sized hepatomegaly in all females. Above mentioned 7 cases are thought to be very significant because 7 cases occupy 35% in 20 cases of abnormal SGOT activity with hepatomegaly. 7) Abnormal SGOT activity was found in 12 cases(4.4%) among 273 cases of hepatomegaly of "not firm" consistency, while it was found in 8 cases(22.2%) among 36 cases of hepatomegaly of "firm" consistency. The difference of incidence of abnormal SGOT activity showed statistical significance(p<0.05). 8) Abnormal SGOT activity was found in 5 cases(17.9%) among 28 cases of spider angiomata with hepatomegaly, while it was found in 10 cases(7.3%) among 166 cases of telangiectasia without spider angiomata with hepatomegaly. Owing to a small number of cases, statistical significance was not recognized, but the incidence of abnormal SGOT activity in spider angiomata cases with hepatomegaly is apt to be higher than that in telangiectasia cases without spider angiomata with hepatomegaly. 9) The incidence of abnormal SGOT activity is apt to be higher with age in male group; abnormal SGOT activity was not found among 4 cases of hepatomegaly in second decade and it was 3.8% in third decade, 4.5% in fourth decade, 9.3% in fifth decade, 17.5% in sixth decade and 33.3% in seventh decade, while the incidence of it was only one case among 67 cases in all females. 10) It is believed that the performance of liver function test to the subjects with hepatomegaly even in ordinary medical examination(the insured amount is low) will give considerable contribution for medical selection of hepatomegaly risk. 11) Age of the insured(young or old), presence of facial telangiectasia or spider angiomata especially and their severity, and consistency of enlarged liver(firm or not) should be considered to increase accuracy in evaluating hepatomegaly risk.

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Effects of Iterative Reconstruction Algorithm, Automatic Exposure Control on Image Quality, and Radiation Dose: Phantom Experiments with Coronary CT Angiography Protocols (반복적 재구성 알고리즘과 관전류 자동 노출 조정 기법의 CT 영상 화질과 선량에 미치는 영향: 관상동맥 CT 조영 영상 프로토콜 기반의 팬텀 실험)

  • Ha, Seongmin;Jung, Sunghee;Chang, Hyuk-Jae;Park, Eun-Ah;Shim, Hackjoon
    • Progress in Medical Physics
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    • v.26 no.1
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    • pp.28-35
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    • 2015
  • In this study, we investigated the effects of an iterative reconstruction algorithm and an automatic exposure control (AEC) technique on image quality and radiation dose through phantom experiments with coronary computed tomography (CT) angiography protocols. We scanned the AAPM CT performance phantom using 320 multi-detector-row CT. At the tube voltages of 80, 100, and 120 kVp, the scanning was repeated with two settings of the AEC technique, i.e., with the target standard deviations (SD) values of 33 (the higher tube current) and 44 (the lower tube current). The scanned projection data were reconstructed also in two ways, with the filtered back projection (FBP) and with the iterative reconstruction technique (AIDR-3D). The image quality was evaluated quantitatively with the noise standard deviation, modulation transfer function, and the contrast to noise ratio (CNR). More specifically, we analyzed the influences of selection of a tube voltage and a reconstruction algorithm on tube current modulation and consequently on radiation dose. Reduction of image noise by the iterative reconstruction algorithm compared with the FBP was revealed eminently, especially with the lower tube current protocols, i.e., it was decreased by 46% and 38%, when the AEC was established with the lower dose (the target SD=44) and the higher dose (the target SD=33), respectively. As a side effect of iterative reconstruction, the spatial resolution was decreased by a degree that could not mar the remarkable gains in terms of noise reduction. Consequently, if coronary CT angiogprahy is scanned and reconstructed using both the automatic exposure control and iterative reconstruction techniques, it is anticipated that, in comparison with a conventional acquisition method, image noise can be reduced significantly with slight decrease in spatial resolution, implying clinical advantages of radiation dose reduction, still being faithful to the ALARA principle.

Follow-up of Children with Chronic Hepatitis B Virus Infection (B형 간염 바이러스 만성 감염 소아의 추적 관찰)

  • Hwang, Sung Hyun;Kim, Jong-Hyun;Kang, Jin-Han;Hur, Jae Kyun;Lee, Kyung Il;Oh, Jin Hee;Lee, Seung Hee;Kyun, Dae
    • Pediatric Infection and Vaccine
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    • v.11 no.1
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    • pp.73-80
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    • 2004
  • Purpose : The serial clinical findings, biochemical results, and serological hepatitis B virus(HBV) markers in Korean children with chronic HBV infection were analyzed to determine the relationships among these factors. Methods : Ninety children have been chosen from those who have visited to the Department of Pediatrics at St. Vincent's Hospital in The Catholic University of Korea from July 1st, 1995 to June 30th, 2000. The sample patients were followed up for over six months. HBV markers and liver function tests were all performed. Results : All children were asymptomatic at presentation. Eighty-three percent of the children had a history of chronic HBV infection in their families. Eighty-one percent were HBeAg positive, 16% were anti-HBe positive, while 3% were all HBeAg and anti-HBe negative. The prevalence of HBeAg among three age groups : 0~5; 6~10; and 11~15 year-old was 90%, 96% and 61% respectively. The prevalence of HBeAg in less than 10 year-old group was significantly higher than 11~15 year-old group(P=0.001). Serum ALT levels were within 40 IU/L in 64% children, 41~80 IU/L in 17%, 81~200 IU/L in 10%, and beyond 201 IU/L in 9%. The percentage of abnormality of ALT levels in HBeAg positive patients was significantly higher than that of HBeAg negative(P=0.036). Eleven of the 73 HBeAg positive children lost their HBeAg and seroconverted to anti-HBe. In these cases, all had transient elevations in ALT levels before HBeAg seroconversions. The annual rates of spontaneous seroconversion of HBeAg and HBsAg were 9.7% and 0.6%, respectively. Conclusion : Recognition of the dynamics of these changes in viral markers and biochemical findings is needed in the selection and evaluation of therapeutic regimens, establishment of treatment, and calling for controlled trials with adequate follow-up. The hepatitis B carrier state may be asymptomatic in children however, continued surveillance of carriers is important to determine the individual adverse prognostic factors of chronic HBV infections.

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Effect of Follicular Fluid on Sperm Swim-up Separation with Sucrose Layer (난포액이 Sucrose 층을 이용한 정자의 Swim-up 분리에 미치는 효과)

  • 김경화;여영근;박영식
    • Journal of Embryo Transfer
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    • v.13 no.3
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    • pp.277-289
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    • 1998
  • To establish a system for sperm swim-up separation through sucrose layer, indiscreet sperm migration should sufficiently to block but movement of sperm shouldn't inhibit. Thus, the effects of sucrose levels in sucrose layer, incubation times and types of sucrose layer on sperm separation were examined. And the results obtained were as follows; 1. Layer of 10mM sucrose inhibited sperm swim-up migration through sucrose layer. 2. Incubation for 25 minutes without sucrose layer significantly increased sperm swim-up migration. However, incubation for 10 minutes to induce swim-up through sucrose layer significantly stimulated sperm migration and maintained sperm movement. 3. There was no significant difference between Type I and Type II in barrier effect of sucrose layer. However, sucrose layer of Type II with shorter distance of barrier was efficient for sampling. To elucidate a function of follicular fluid on sperm chemotaxis using in vitro system of sucrose layer of Type II and incubation for 10 minutes, the effects of dilution, heat treatment, and protein and lipid extracts of follicular fluid on sperm swim-up separation were examined. And the results obtained were as follows; 4. Follicular fluid stimulated sperm migration and movement, and significantly-attracted capacitated-sperm at 10% level. 5. Follicular fluid heated at 55$^{\circ}C$ for 30 minutes maintained the effect of follicular fluid stimulating sperm migration and movement. 6. Follicular protein stimulated sperm movement that was reduced by filtration of the protein. 7. Follicular lipid didn't significantly stimulate sperm migration and movement. 8. Both of follicular protein and lipid reduced the effect of follicular fluid stimulating sperm migration and movement. In conclusion, sucrose layer could be used for a barrier against indiscreet sperm migration by swim-up. And follicular fluid stimulated migration and movement of sperm and attracted capacitated-sperm through sucrose layer. Especially, heat-resistant protein of follicular fluid stimulated sperm migration.

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Effect of Season on Testis Function and Freezing and Fertilizing Ability of Spermatozoa in Korean Native Goat I. Seasonal Changes in Semen Characteristics and Freezing and Penetrating Ability of Sperm (한국재래산양에서 계절이 정소기능, 정자의 내동성 및 수정능력에 미치는 영향 I. 정액성상과 정자의 내동성 및 난자침입능력의 계절적 변화)

  • Kim, C.K.;Chung, Y.C.;Kim, K.S.;Yoon, J.T.;Lee, J.H.;Chung, Y.H.;Choi, S.H.;Kim, H.Y.;Kim, S.;Kwon, C.J.
    • Korean Journal of Animal Reproduction
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    • v.17 no.4
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    • pp.311-323
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    • 1994
  • This study was conducted to observe seasonal and individual changes in semen characteristics and sperm freezability, and sperm penetration into zona-free hamster eggs in Korean native goats. Buck response and change in semen characteristics to electrical stimulations was evaluated for four seasons throughout 2 years and percentage of motile sperm and normal apical ridge acrosome was investigated after equilibration and thawing for 4 seasons with 5 bucks. Sperm penetration rate was evaluated for 4 bucks. 1. Probe insertion at depth of 7cm and repeated stimulation for 3 sec was more effective(P<0.05) in buck response and semen collection than those of other conditions. 2. Semen characteristics from electrojaculation was signficantly(P<0.005) higher in spring and fall for semen volume, in spring and summer for sperm concentration and in fall for sperm motility than those in other seasons, respectively. However, there were no differences in total sperm among seasons. 3. Buck response to electrical stimulation showed significant difference(P<0.05) among individuals in all 3 seasons except winter. Significant individual difference in semen volume was only in spring and summer, but there was no indivudual difference in sperm concentration and total sperm in all season. 4. Washing of semen before freezing treatment was greatly(P<0.05) beneficial to sperm motility after thawing, no matter whether ejaculates exhibit egg yolk coagulation or not. 5. Sperm motility after glycerol equilibration was significantly(P<0.05) low in summer semen and motility after thawing was greatly(P<0.05) higher in winter semen than in other seasons. Freezability of unwashed sperm was significantly difference among bucks, but a yearly freezability of washed sperm after chilling and thawing were no differences among bucks and percentage of normal apical ridge acrosome were not different among seasons and bucks. 6. There was no significant difference in sperm motility after thawing between egg yolk levels in summer, although 20% level gave more higher motility than 5% level. 7. In summer, 3.2% glycerol and 3-h equilibration gave greatest percentage(P<0.05) of sperm motility and normal apical ridge acrosome after thawing. 8. Sperm penetration rate into zona-free hamster eggs was not different between bucks and seasons. Overall, it is concluded that to obtain maximum sperm output and successive semen freezing by electrojaculation method, buck selection with good response in all season could be basically considered and that seasonal effect on sperm freezability was more greater than that of individual bucks.

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Generation of a Mammalian Gene Expression Vector Using Bovine Viral Diarrhea Virus (Bovine Vira1 Diarrhea Virus를 이용한 포유동물세포 발현벡터의 개발)

  • 이영민
    • Korean Journal of Microbiology
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    • v.38 no.2
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    • pp.86-95
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    • 2002
  • As a result of genome projects, the research to elucidate the function of a protein of interest has recently been well-recognized. In order to facilitate functional genomics, a useful mammalian gene expression vector is required. Using an infectious CDNA clone of BVDV pNADLclns-, we have developed a mammalian gene expression vector. In this study, a replication-competent full-length infectious CDNA clone containing puremycin acetyltransferase (pac) gene (pNADLclns-/pac) was successfully generated. The viral RNA replication and viral protein NS3 synthesis were examined by detecting metabollically $^{32}P$-labelled genomic viral RNA and immunoblotting with a mouse anti-NS3 antibody. To generate viral replicon as an expression vector, we examine if the viral structural genes (C, E0, El, E2) are required for viral replication by deletion analysis. As a result, all of the structural proteins are dispensable for viral replication per se, but essential for infectious viral particle formation. Based on our deletion analysis, we have generated a replication-competent BVDV viral replicon (pNADLclns-/pac/${\Delta}S$), whose structural genes are all deleted. In addition to NADLclns- /pac/${\Delta}S$, NADLclns-/ luc/${\Delta}S$ viral replicon containing luciferase gene as a reporter was constructed and fecund to be replication-compotent in HeLa and BHK cells as well as MDBK cells. Therefore, BVDV viral replicon developed in our study will be a useful tool to express a protein of interest in various mammalian cells.