For the safety extirpation in case of acute pulpitis with painless procedure, lots of pulp devitalizers have been designed for a long time. Authors have manufactured experimental pulp devitalizer with adding some other constituents for main components of paraformaldehyde and local anesthetics. The purpose of this study was to observe the histopathologic tissue response in pulp tissues by applying newly developed safety pulp devitalizer to the human tooth. For this experiments 5 human teeth in 4 patients (ages of 26 to 49) were used. In case of acute pulpitis with pulp exposure, divided into two groups; One group, carious dentin removed, and then was applied newly developed devitalizer directly to exposed small pulp tissues. Other group, was exposed the pulp chamber, pulpotomized and then the devitalizer was applied to remaining pulp tissues. The teeth were extracted on 3rd and 7th day after operation respectively. For the control group, Depulpin? was used as pulp devitalizer. All the extracted teeth were fixed in 10% neutral formalin solution, decalcified in Plank-Richlo solution, embedded in paraffin, sectioned 6-8㎛ in thickness, stained with hematoxylin-eosin stain method, and examined under microscope. Attained results were as follows; 1. There were no difference in histopathologic aspects either exposed or not pulp chamber, the extent of necrosis of pulp tissue and destruction of odontoblast was similar to that on the 3rd day of control group and both the 3rd and 7th day of the experimental group. 2. For the necrosis of pulp tissue and destruction of odontoblast on the 3rd day of control group exposed pulp chamber, was similar to that on the 3rd day of experimental group exposed small pulp tissue. The experimental pulp devitalizer could reduce the side effects, which reduced the amount of paraformaldehyde components, adding other constituents, reduced the duration of pulp devitalization, and useful whether exposed or not the pulp chamber.

To investigate the effect of co-transfer of trophoblastic vesicle (TV) with frozen-thawed in vitro Produced (IVP) bovine embryo on pregnancy rate, IVP blastocysts were transferred to synchronized recipients. Elongated blastocysts were recovered at Day 13 to 15, and dissected more than 4 pieces to removed the embryonic disc. Throphoblastic fragments were cultured for 48 hours to make throphoblastic vesicles (TVs). TVs were cryopreserved in ethylene glycol or vitrification solution and frozen-thawed TVs were co-transferred to recipients with frozen-thawed IVP embryos. 1 The recovery rate of elongated blastocyst on Day 13 to 15 was 22.5% (18/80) and the size of recovered elongated blastocysts was 0.2∼5.0mm. 2. Eighteen elongated blastocysts were dissected into 88 pieces and 61.4% of those pieces were formed to TV (54/88) 3. The viability of frozen-thawed TV in ethylene glycol was higher than in vitrified solution (92.8% vs. 68.8%) 4. The pregnancy rate in co-transfer with frozen-thawed TV and IVP blastocyst was better than transfer only IVP blastocysts (50.0% vs. 23.1%).

본 시험은 원형베일러를 이용한 생볏짚 사일리지의 조제 가능성을 구명하고 적정 첨가제를 선발하기 위하여 1997년 10월부터 1998년 6월까지 축산기술연구소 초지사료과에서 실시하였다. 첨가제는 생볏짚을 원형베일로 만들기전 무처리, 개미산, 당밀, 당밀+요소 및 젖산균제 등 5처리를 두고 난괴법 3반복으로 수행하였으며 사일리지 품질과 가축 섭취량 등을 조사하였다. 조단백질 함량은 당밀+요소 처리구에서 가장 높았으며 소화율은 당밀 및 젖산균 처리구에서 증가하였다. 건물률에 있어서는 개미산 처리구가 가장 높았고 대조구에서 가장 낮게 나타났으며 첨가제 처리간에는 차이가 없었다. 그러나 산도(pH)는 당밀 및 젖산균제 처리구에서 대조구보다 낮게 나타났다. 유기산 함량은 전체적으로 2%이하로 낮게 나타났으며, 젖산 함량은 당밀 및 젖산균제 처리구에서 유의적으로 증가하였고(P<0.05) 낙산 함량은 감소하였다. 암모니아태 질소의 함량은 당밀+요소 처리구에서 유의적으로 높았으며 당밀 및 젖산균제 처리구에서 10% 이하로 낮게 나타났다. 7일간의 가축 급여시험에서는 젖산균제를 처리한 생볏짚 원형베일 사일리지에서 두당 섭취량이 무처리 원형베일 사일리지와 건조볏짚에 비해 높게 나타났다. 생볏짚 원형베일 사일리지 생산비는 수거면적이 넓어짐에 따라 생산비가 크게 낮아졌다. 이상의 결과를 종합하여 볼 때 생볏짚을 원형베일 사일리지로 조제시 당밀 또는 젖산균제를 첨가할 때 가장 우수한 사일리지를 조제할 수 있었고 젖산균제 처리시 가축 섭취량도 증가되는 것으로 나타났다.

This experiment was carried out to investigate effects of herbicide application method on Calysteria jcqoonica control and corn yield at the forage experimental field, grassland and forage crops division, National Livestock Research Institute, RDA, Suwon

The present study was carried out to investigate the effects of co-culture cells and growth factors on in vitro culture of Korean native cattle(KNC) embryos fertilized in vitro. Two-eight cell embryos were cultured in vitro using 4 types of co-culture cells and 3 growth factors singly or in combination. The results were as follows, In the co-culture of 2~8 cell embryos with bovine oviductal epithelial cell(BOEC), granulosa cell(BGC), uterine epithelial cell(BUEC) and mouse embryonic fibroblast (MEF) monolayers, the developing rate to blastocysts was significantly(P<0.05) higher with BUEC(32.1%) than with MEF(15.3%), BGC(13.2%) and non co-culture control(11.6%). When the morula co-cultured with BOEC for 5 days following in vitro fertilization were co-cultured with BOEC continuously or with BUEC, respectively, the developing rate to blastocysts was higher with BUEC(73.9%) than with BOEC(56.0%). To examine the effects of growth factors on in vitro development of 2~8 cell embryos, epidermal growth factor(EGF), transforming growth factor-l(TGF-l) and insulin-like growth factor-1(IGF-1) were added singly or in combination to TCM 199 maturation medium with respective concentration. In a addition of each 10, 30 and SOng /rnl EGF, the developing rate to blastocysts was the highest in lOng /ml EGF(25.3%). In addition of each 1, 2 and Sng /mi TGF-1, the developing rate to blastocysts was the highest in lng /ml TGF-1(28.8%). In addition of each 50, 100ng/ml JGF-l, the developing rate to blastocysts was higher in 100ng/ml IGF-l(16.5%) than in SOng/mi IGF-1(12.9%). When lOng /ml EGF and lng /ml TGF-l was added singly or in combination, the developing rate to blastocysts was similar in groups added singly or in combination with EGF and TGF-l (23.l~24.6%), although higher than in control(16.7%). In the co-culture of 2~8 cell embryos Wth BOEC + each 10, 30 and 5Ong /rnl EGF, the developing rate to blastocysts was significantly(p<0.05) higher in BOEC + long /ml EGF(32.3%) than in BOEC + 3Ong /ml EGF(18.9%) and BOEC + song /ml EGF(9.7%). In the co-culture of 2~8 cell embryos with BOEC + each 1, 2, Sng /ml TGF-l the developing rate to blastocysts was higher in BOEC + Sng/rnl TGF-l(28.2%) than in BOEC + lng /ml TGF-l(21.7%) and BOEC + 2ng/ml TGF-l(21.4%). In summary, higher developing rate to blastocysts were obtained with co-culture of BUEC for co-culture system, with addition of lOng /ml EGF or lng /ml TGF-l for growth factor culture system, and with co-culture of BOEC + lOng /ml EGF or BOEC + Sng /ml TGF-l for co-culture + growth factor culture system.

This study was carried out to investigate the effect of sperm concentration of 5ml maxi-straw on farrowing rate and number of pigs born alive per litter in deep frozen boar semen. We did not find out the effect of sperm concentration on post-thaw sperm motility and NAR acrosome. However, farrowing rate and number of pigs born alive per litter of 7. 5 x 10˚ /5ml and 10.0 x 10˚ /5m1 sperm concentrations were higher than those of 5. 0 /10˚ /5ml sperm concentration.

ZnO-Bi2O3-CoO-Sb2O3와 ZnO-Bi2O3-CoO-Sb2O3-Cr2O3계에서 미세구조 변화 및 전기적 특성에 미치는 개재물의 영향을 조사하였다. 소결동안에 ZnO입자 성장은 스피넬 입자들에 의해 제어되었으며, 스피넬 입자들의 양의 증가에 의해 입자성장은 감소하였다. Cr2O3(0.5mol%)의 첨가는 비직선성지수에는 큰 영향을 미치지 못하였으며 임계전압(breakdown voltage)을 증가시켰다. 계산에 의해 구한 장벽전압은 ZnO-Bi2O3-CoO-Sb2O3와 ZnO-Bi2O3-CoO-Sb2O3-Cr2O3 계에서 각각 3.1V와 2.9V이었다.

본 연구의 목적은 최근 증가하는 사이버 괴롭힘 사안처리과정에서 교사가 인식하는 어려움을 탐색하여, 사이버 괴롭힘의 실태 및 교사의 상호작용 전략에 대해 파악하고 효과적인 접근 및 해결방안을 제시하는 것이다. 이를 위해 질적 연구 방법인 근거이론(Grounded Theory)을 사용하여 사이버 괴롭힘 사안처리과정에서 교사가 인식하는 어려움을 중심으로 분석하였고, 연구 참여자는 의도적 표집(purposive sampling)을 통해 최근 2년 내에 사이버 괴롭힘 사안처리 경험이 있는 서울과 경기도 지역의 9명의 중 ·고등학교 교사를 대상으로 선정하였다. 분석자료는 참여자들과 일대일 심층면접을 통해 개방코딩(open coding), 축코딩(axial coding), 선택코딩(selective coding)의 세 과정의 분석을 거쳤으며, 분석 결과 133개의 개념과 56개의 하위 범주 및 25개의 범주를 바탕으로 도출된 패러다임 모형(paradigm model)을 제시하였다. 이를 통해 청소년의 사이버 괴롭힘 사안 처리과정에서 교사가 인식하는 어려움은 사이버매체와 사이버공간에서 나타나는 청소년특성 요인에 기인하고 있음을 확인하였고, 이에 따른 어려움을 인식한 교사가 학생과 어떻게 상호작용하고 대처하는지를 탐색하였으며, 긍정적 및 부정적인 측면에서 확인된 결과를 정리하였다. 이들의 실제 경험에 근거하여 분석된 결과에서 제시한 패러다임 모형을 바탕으로 학교에서 사이버 괴롭힘의 사건을 처리해나가는 과정에서 교사가 겪는 어려움을 구체화시킨 점에서 의의를 지니며, 학교현장에서 앞으로의 실천적 해결을 위한 기초 자료로 활용할 수 있다.

In this study, the seismic performance of a Low-rise Pilotis Building with Eccentric Core is investigated. Low-rise Pilotis Buildings are very popular in Korea, but regarded as very weak structure to earthquake.

In this study, the seismic performance of a Low-rise Pilotis Building with Central Core is investigated. Low-rise Pilotis Buildings are very popular in Korea, but regarded as very weak structure to earthquake.

Recently, Earthquake occurrence in korea has become frequent, and the seismic safety of low-rise piloti buildings becomes more and more important. In this study, the differences in seismic performance between before and after reinforced by concrete filled steel tube (CFT) of low-rise central core type piloti building structures were compared.

Recently, Earthquake occurrence in korea has become frequent, and the seismic safety of low-rise piloti buildings becomes more and more important. In this study, the seismic retrofit method of low-rise eccentric core type piloti building structures using concrete filled steel tube (CFT) columns was analysed and verified for seismic performance.