High-speed machining is one of the most effective technologies to improve productivity. Because of the high speed and high feed rate, high-speed machining can give great advantages for the machining of dies and molds. High speed machine tool makers try to

Epithelial-mesenchymal interaction is well known to have an importance during the organ development as well as cell growth and differentiation. However, in vitro experimental model is not well developed to reproduce in vivo cellular micro-environment which provide a epithelial-mesenchymal interaction. The aims of this study were to develop and evaluate the in vitro experimental model that maintains epithelial-mesenchymal interaction by organotypic raft culture, and to characterize biologic properties of three-dimensionally reconstituted human normal oral kertinocyte(NHOK) and immortalized human oral keratinocytes(IHOK) by histological and immunohistochemical analysis. The results were as follows; 1. Best condition of three dimensionally reconstituted IHOK & HaCaT cells are 14 days air-exposure cultivation, 3 days of submerged state, and dermal equivalent consisting type I collagen and IGF cells. 2. In comparison to IHOK, there was better preservation of the overall epidermal strucutures in oral cracioma cells (HN30) & HaCaT cells by organotypic cultures. But orgnaotypic co-culture of the normal keratinocyte showed the thinnest epithelial layer formation. 3. PCNA was detected primarily in the basal layer of normal mucosa and NHOK, whereas was shown throught the epithellium except surface layer of IHOK cells, and it's expression was similar to that of CIS of biopsied patient's tissue 4. Involucrin is expressed in the upper layer of oral mucosa and NHOK raft, but staining for involucrin was induced in the IHOK rafts indicating differentiation is incomplete, and the staining pattern in the IHOK raft was not uniform. 5. Normal oral keratinocyte raft showed weak immunostaining for p53, and p53 expression of IHOK raft increased rahter than in NHOK. In organotypic cultures of normal cells and IHOK, p53 expression was restricted to the proliferative part of epithelium. This is consistent with expression pattern in biopsy specimens of the normal and CIS tissue. 6. In artifically reconstructed NHOK, the pattern of keratin staining showed both similarity and differences from that of intact normal mucosa. An obvious difference was increased expression of CK10 & CK19, and decreased expression of CK6 in a reconstructed NHOK rather than in normal mucosa, and similar expression was in CK4 and CK16. 7. CK19 & CK16 were strongly positive in HPV immortlaized keratinocyte rafts rahter than in NHOK, an indicator of premalignant or malignant changes, while CK10 & CK6 were decreased, and organotypic cultures of IHOK express was similar keratin expression as epithelial dysplasia or CIS tissue. These results suggest that three-dimensional organotypic co-culture of normal oral & immortalized keratinocytes with dermal equivalent consisting type I collagen and fibroblasts results in similar morphologic and immunohistochemical characteristics to in vivo patient specimens. Thus this organotypic system can be used for studing mechanism of epitehlial-mesenchymal interaction in particular regulating epidermal diffenentiation and morphogenes

곡면가공에서 5축 가공은 복잡한 형상의 공작물에 대한 가공의 필요성이 증대되면서 3축가공보다 자유곡면 가공을 위한 시도와 연구가 활발히 이루어지고 있으나 가공 시 충돌과 간섭의 문제를 해결해야하는 어려움으로 공구경로 생성에 많은 문제점을 내포하고 있다. 이러한 문제를 해결하고자 최근에는 다양한 5축 CAD/CAM Software가 개발 되었고 이를 활용하는 사례가 늘어나고 있다. 본 논문에서는 자유곡면으로 이루어진 대표적인 형상인 Impeller의 복잡한 형상을 CAD Software를 이용하여 모델링 하였고, CAM Software로 공구 경로를 생성 및 검증하였으며 5축 가공기로 직접 가공하였다.

현실적으로 최근 공작기계의 고속화가 급속히 진전되고 있는 것이 세계적인 기술 추세이다. 이와 맞물려 고속공작기계 내지는 고속가공시스템 표준 평가방법의 정립이 필요하다. 이에 본 논문은 고속가공기의 특성이나 성능평가 방법을 위해, 가공방향 조도상차이, 표면조도, X,Y축 이송에 의한 직각도 및 Z축 떨림, 상한돌기, 직경감소와 미소지정, 열변형랑, 가공시간등의 테스트항목을 선정하여 육안검사시편을 개발 및 가공함으로써, 고속가공기의 특징을 분석하여 최적의 기계성능을 활용할 수 있게 하고자 한다.

We used three-dimensional Matrigel culture system to examine the morphognesis of normal and malignant salivary glands cell in vitro including acinar cells(AC), myoepithelial cell(MC), salivary gland adenocarcinoma cells(SGT), mucoepidermoid carcinoma cells(MEC), and immortalized human salivary gland cells(HSG). For this purpose, normal and salivary gland tumor cells cultured in 3-D Matrigel, and characterized histologically and immunohistochemically, compared with same cells grown on monolayer culture and patient tissue from biopsy. 1. In three-dimensional Matrigel culture, HSG cells form acinar structure, SGT cells shows duct like structure, and other AC, MC and MEC cells dont' form any structure , and their morphology was different from that of monolayer cells. 2. Matrigel involved cell proliferation at a similar pattern to cells on plastic monolayer cell cultures, and monolayer cell revealed higher cell viability than that of Matrigel cultured cells. 3. All salivary glands cells on Matrigel or monolayer showed strong PCNA expression, and there is no expression difference in these cells. But some cells including myoepithelial cells in normal and salivary gland tumor tissue showing PCNA lavelling, so there is PCNA expression difference among normal and tumor tissue cells. 4. Actin expression was noted in AC cells on Matrigel, were rare expressed in the other cells except in MEC cells, and was present in myoepithelial cell and ductal cells of normal gland tissue. There is actin expression difference between tissue and cultured cells . 5. S-100 immunoreaction was moderateively positive in MC cells of monolayer culture, myoepithelial cells of normal tissue and pleomorphic adenoma, all cancer cells of mucoepidermoid carcinoma tissue, but significantly decreased in all salivary cells on Matrigel. 6. TGase 2 expression was prominent in MC cells of monolayer and Matrigel cultured, in myoepithelial cells of normal gland and pleomorphic adenoma, epidermoid cells of mucoepidermopid carcioma, and strong reaction in MEC and AC cells of monolayer and Matrigel cultured. 7. Expression of CK in monolayer culture showed strong reaction to CK6 in all sailvary gland cells, and mild reaction to CK10 and CK16 for all salivary cells, CK16 and CK19 expression in monolayer culture was similar to that of Matrigel culture. 8. CK6 and CK10 expression was strongest in AC and MC cells on Matrigel, and CK 4 was negative reaction in AC, SGT, MEC cells, strong reaction in MC cells but mild in SGT cells on Matrigel. Expression of CK was rare in HSG cells compared with other salivary gland cells, CK16 was prominent in SGT cells, CK10 and CK16 showed strongest expression in MEC cells of Matrigel. 9. Monolayer culture of HSG cell shwoing strong reaction to CK6, moderate to CK19 and mild to the others CK, but 3D cultured HSG cells reveal mild expression to CK16, and rare to others CK, intercallated duct in normal gland tissue showing strong to CK19, and mild to the others Ck, so there are CK expression difference in tissue, monolayer and 3-D cultured cells. 10. Monolayer culture of MEC cells represent strong reaction to CK6, mild to other CK, 3-D cells showing increased CK expression including CK6, epidermoid cells and intermediate cells in mucoepidermoid carcinoma tissue reveal positive to CK6 and CK16, mucous cell positive to CK10 and CK19, so Matrigel showed similar CK pattern compared to mucoepidermoid carcinoma tissue rather than monolThese data indicate that the interaction of salivary gland cells with basement membrane is an important factor in salivary gland development and cytodifferentiation, so this model system will be useful to study acinar or ductal differentiation in vitro.ayer cultred.

고속 가공은 고속가공기마다 자체의 기계적 특성이나 강성이 모두 다르므로 공작기계를 생산하는 회사 자체에서 자사의 장비가 가장 좋은 특성을 낼 수 있는 조건을 알아내기 위해서 기계의 여러 가지 항목을 확인하여 만든 육안검사 시편을 개발하여 기계의 특성을 파악한다. 이에 본 논문은 고품위가공의 한 방법으로 기계적 특성이나 성능 테스트규명을 위해, 표면조도, overshoot, 상한돌기, 직경감소와 미소지정, 열변형랑, 가공시간, 상.하방향 조도상차이등의 테스트항목을 선정하여 육안검사시편을 개발 및 가공함으로써 고속가공기의 특징을 분석하여 최적의 기계성능을 활용할 수 있게 하고자 한다.

우리나라에서 생산되고 있는 60여종의 약용식물의 지방산 조성을 조사하여 식물체의 부위 와 종류에 따른 지방산 조성의 특성을 관찰한 결과 아래와 같은 결과얻었다. 1. 달맞이꽃종자, 컴프리잎, 지치뿌리에서 각각 총지방산함량의 9.1, 3,5, 7,2%의 GLA가 검출되었으며 달맞이 꽃종자가 컴프리잎이나 지치뿌리보다 GLA의 절대량이 많았다. 2. 들깨종자, 참깨종자, 호박종자등의 지방산이 양(量)과 불포화도면에서 좋은 자원임이 확인되었다. 3. 식물체의 잎, 줄기, 뿌리에서의 지방산조성은 종자의 경우에 비하여 18 : 3의 분포 비율이 현저히 높게 나타났으며 18 : 0의 비율은 비교적 같게 나타났다.