• Biotechnology and Bioprocess Engineering:BBE
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• 제7권3호
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• pp.163-170
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• 2002

This report describes the use of a transtubular bioreactor to study the relative effects of diffusion versus perfusion of medium on antibody production by a hybridoma cell line. The study was performed with a high-density cell culture maintained in a serum-free, low-protein medium for 77 days. It was determined that the reactor possessed a macro-mixing pattern residence time distribution similar to a continuous stirred tank reactor (CSTR), However, due to the arrangement of the medium lines in the reactor, the flow patterns for nutrient distribution consist of largely independent medium path lengths ranging from short to long. When operated with cyclic, reversing, transtubular medium flow, some regions of the reactor (with short residence times) are more accessible to medium than others (with long residence times). From this standpoint, the reactor can be divided into three regions: a captive volume, which consists of medium primarily delivered via diffusion; a lapped volume, which provides nutrients through unilateral convection; and a swept volume, which operates through bilateral convection. The relative sizes of these three volumes were modified experimentally by changing the period over which the direction of medium flow was reversed from 15 min (larger captive volume) to 9 h (larger swept volume). The results suggest that antibody concentration increases as the size of the diffusion-limited (captive) volume is increased to a maximum at around 30 min with a sharp decrease thereafter. As reflected by changes in measured consumption of glucose and production of lactate, no significant difference in cellular metabolism occurred as the reactor was moved between these different states. These results indicate that the mode of operation of the transtubular bioreactor may influence antibody productivity under serum-free, low-protein conditions with minimal effects on cellular metabolism.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
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• pp.250-253
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• 2000

We researched effects of growth on initial inoculum size, liquid volume, and medium feeding rate etc. Cell suspension inoculated at low cell concentrations showed a typical growth reduction, whereas root cultures showed an improvement in growth. In this paper, Hairy roots showed high growth rate at 0.4 % inoculum size and 100 mL liquid volume in 250 mL flask cultures.

• 대한기계학회논문집B
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• 제28권5호
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• pp.580-586
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• 2004

The ray effects of finite volume method (FVM) or discrete ordinate method (DOM) are known to show a non-physical oscillation in solution of radiative heat transfer on a boundary. This wiggling behavior is caused by the finite discretization of the continuous control angle. This article proposes a combined procedure of the Monte-Carlo and finite-volume method (CMCFVM) for solving radiative heat transfer in absorbing, emitting, and an-isotropically scattering medium with an isolated boundary heat source. To tackle the problem, which is especially pronounced in a medium with an isolated heat source, the CMCFVM is suggested here and successfully applied to a two-dimensional circular geometry.

• 한국진공학회지
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• 제12권4호
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• pp.207-213
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• 2003

중진공 국가표준기의 자동화를 위한 하드웨어 및 측정 프로그램 개발에 관한 연구를 수행하였다. 이 장치는 부피가 서로 다른 여러 개의 진공용기, 배기장치, 진공게이지, 온도계, 그리고 밸브 등 많은 부품들로 구성되어 있을 뿐만 아니라 복잡한 측정방법 때문에 자동화가 꼭 필요하다. 개발한 자동화 장치의 성능 평가를 위하여 진공용기의 부피율을 측정하고 용량형 격막식 진공게이지를 교정해 보았다.

• The Korean Journal of Pain
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• 제31권2호
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• pp.125-131
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• 2018

Background: The thoracic transforaminal epidural block (TTFEB) is usually performed to treat herpes zoster or postherpetic neuralgia (PHN). Especially, multiple segmental involvements and approximate contrast medium spread range, according to volume, help to choose the proper drug volume in the transforaminal epidural block. This study investigated the contrast medium spread patterns of 1-ml to 3-ml TTFEBs. Methods: A total of 26 patients with herpes zoster or PHN were enrolled in this study. All participants received 1 ml, 2 ml, or 3 ml of contrast medium. Results were divided into Groups A, B and C based on the volume (1, 2, or 3 ml), with n = 26 for each group. After the injection of contrast medium, the spread levels were estimated in both the lateral and anteroposterior (AP) images using fluoroscopy. Results: The cephalad spread of contrast medium in the lateral image as expressed by the median (interquartile range) was 2.00 levels (1.00-2.00) for Group A, 2.50 (2.00-3.00) for Group B, and 3.00 (2.00-4.00) for Group C. The caudal spread level of contrast medium was 1.00 (1.00-2.00) for Group A, 2.00 (2.00-3.00) for Group B, and 2.00 (2.00-3.00) for Group C. There was ventral and dorsal spread of the 3-ml contrast medium injection in 88% (23/26) of cases in the lateral image. Conclusions: Injection of 3 ml of contrast medium through the foramina spread 6 levels in a cephalocaudal direction. Spread patterns revealed a cephalad preference. TTFEB resulted in dorsal and ventral spread in a high percentage of cases. This procedure may be useful for transferring drugs to the dorsal and ventral roots.

• 한국수정란이식학회지
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• 제31권1호
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• pp.27-32
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• 2016

This study was conducted to evaluate the effects of different volume ($100{\mu}l$ vs. 2 ml) of microdrop culture on B6D2F1 mice oogenesis. In the present study, B6D2F1/CrljOri $F_1$ mice were utilized in order to maximize oogenesis. Also we used TCM-199, Dulbecco's medified Eagle's medium (DMEM), embryo culture medium (Fertilization medium, Cleavage medium, Blastocyst medium), G series medium and One step medium. Blastulation rate was not different between groups ($58.4{\pm}2.9%$ vs. $61.2{\pm}4.8%$). Zona hatched rate ($38{\pm}15.4%$ vs. $27{\pm}3.4%$) and attached rate ($55{\pm}13.9%$ vs. $46{\pm}3.9%$) did not differ by the volume of culture media. Total cell numbers ($59.8{\pm}9.7$ vs. $70.3{\pm}8.7$), ICM cell numbers ($15.8{\pm}0.6$ vs. $16.8{\pm}1.5$), TE cell numbers ($44.0{\pm}9.7$ vs. $53.6{\pm}7.3$), % ICM ($26.4{\pm}2.9%$ vs. $23.8{\pm}3.3%$) and ICM:TE ratio ($1:2.8{\pm}0.4$ vs. $1:3.2{\pm}0.6$) were not different between groups (i.e., $100{\mu}l$ vs. 2 ml). These results show that the capacity of the culture medium did not effect the cell numbers of B6D2F1 mice blastocysts. In summary, these results can provide fundamental data to maximize culture condition for in vitro fertilization on B6D2F1 mice.

• Journal of Plant Biotechnology
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• 제37권4호
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• pp.494-504
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• 2010

본 연구에서는 고추의 소포자 배양 시 전처리 후 배지의 교환 여부, 배양 후 새 배지의 첨가 및 2층배지 사용시 하층고체배지의 양이 배의 생산에 미치는 영향을 조사하였다. 고온 전처리 후 배양배지를 첨가하여 배양하는 것보다 사용한 전처리 배지를 새 배양 배지로 교환하여 배양 하는 것이 배의 생산에 효과적 이었으며, 고온전처리 기간은 1일이나 2일에 비해 3일이 효과적 이었다. 배양 후 새 배지의 첨가는 약전처리 시에는 효과가 없었으나 소포자 전처리 시에는 배의 유기와 발달 모두 크게 향상되었다. 새 배지의 첨가 시기는 배양 4일 후가, 첨가 횟수는 1회가 배의 생산에 가장 효과적이었다. 한편 2층배지 사용 시 첨가하는 새 배지의 양은 1.5 ml이 효과적이었으며 이보다 많은 양을 첨가하는 경우 배의 발생과 발달 모두 저하되었다. 액체배지 사용 시에 비해 2층배지 사용 시 배의 발달이 좋았다. 또 2층배지 사용 시 하층고체배지의 양이 3 ml 일 때 보다는 5 ml이나 7 ml일 때 배의 발생은 감소하였으나 배의 질이 향상되었다. 이와 같은 결과들은 고추에서 다수의 정상자엽배를 생산 할 수 있는 소포자 배양시스템을 확립하는데 중요한 기초자료가 될 것이다.

• Reproductive and Developmental Biology
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• 제29권3호
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• pp.145-147
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• 2005

Autocrine or paracrine mediators released by the early embryo are implicated in the support of embryonic development. Their mechanisms and optimal embryo density in the medium, however, are uncertain. This study was conducted to establish the optimal embryo density and culture medium volume in mouse parthenogenetic embryo culture. In experiment 1, culture of parthenogenetirally activated oocytes at a concentration of $2{\~}4$ embryos/${\mu}L$ significantly improved development to the blastoryst stage ($72{\%}{\leq}$) compared with culture at the lower ($0.2{\~}1$e mbryos/${\mu}L,\;0\~37.5\%$) and the higher ($5{\~}6$ embryos/${\mu}L,\;30\~53\%$) concentration for 120 h when the oocytes were cultured in a 5 ${\mu}L$ drop under mineral oil In experiment 2, the embryos cultured at a concentration of $2{\~}4$ embryos/${\mu}L$ in a 10 ${\mu}L$ drop ($81.1{\%}$) showed significantly higher blastocyst rates than those in a 5 ${\mu}L$ drop ($68.5{\%}$). This study optimizes in vitro culture condition by modifying embryo density and the volume of culture medium It may give appropriate level of autocrine and/or paracrine factors to enhance viability and subsequent normal development of mouse parthenogenetic embryos in vitro.

• 대한가정학회지
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• 제34권3호
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• pp.47-57
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• 1996

Ther purpose of this study was to investigate the perceptual differences in brand images of national medium-low price casual clothing according to purchase volume and brand loyalty. Additionally, differences between Seoul and County of Chungnam in purchase volume of each brand of medium-low priced casual, information source and companion in purchasing the brands were analyzed. The questionnaires were administered to 540 college student living in Seoul and County of Chungnam, and the method used to analyze the data were frequency, factor analysis, and t-test. The results were as follows: 1) Perceptual mapping showed that preference ranks among the six brands were same regardless of purchase volume and brand loyalty, but heavy users and loyal consumers to medium-low priced casual brands had more favorite brand image than light users and non loyal consumers. 2) Those who live in County of Chungnam purchased all six brands more than those who love in Seoul with the exception of Hunt. Information sources such as catalogs and celebrity were more used in County of Chungnam. Most accompanied shopping alone both in Seoul and County of Chyngnam, however family members were more influential in Seoul, whereas the same sex friends were in County of Chyngnam.

• 한국수학교육학회지시리즈D:수학교육연구
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• 제19권4호
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• pp.267-278
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• 2015

The study is about the influence of literal, symbolic and graphics languages on mathematics reading. The results show that the scores of symbolic language volume are significantly lower than that of literal language volume. The abstractness of the mathematical symbols will not have a significant impact on the students with excellent mathematical academic, but as for the medium and poor students, abstract mathematics symbols will cause their cognitive impairment. Due to picture-superiority-effect, the test scores of the graphics language volume are significantly higher than that of the symbolic language volume. Graphics language will have a significant impact on the excellent and medium students, but has no impact on the poor students.