Background : Both Panax ginseng Meyer and Panax quinquefolius are obligate shade-loving plants whose natural habitats are broadleaved forests of Eastern Asia and North America. Panax species are easily damaged by photoinhibition when they are exposed to high temperatures or insufficient shade. In this study, a cytohistological study of the leaf structures of two of the most well-known Panax species was performed to better understand the physiological processes that limit photosynthesis. Leaves of ginseng plants grown in soil and hydroponic culture were sectioned for analysis. Methods and Results : Leaf structures of both Panax species were observed using a light microscope, scanning electron microscope, and transmission electron microscope. The mesostructure of both P. ginseng and P. quinquefolius frequently had one layer of noncylindrical palisade cells and three or four layers of spongy parenchymal cells. P. quinquefolius contained a similar number of stomata in the abaxial leaf surface but more tightly appressed enlarged grana stacks than P. ginseng. The adaxial surface of the epidermis in P. quinquefolius showed cuticle ridges with a pattern similar to that of P. ginseng. Conclusion : The anatomical leaf structure of both P. ginseng and P. quinquefolius shows that they are typical shade-loving sciophytes. Slight differences in chloroplast structure suggests that the two different species can be authenticated using transmission electron microscopy images, and light-resistant cultivar breeding can be performed via controlling photosynthesis efficiency.

방사광 X-선 현미경은 임상실험에 유용한 도구로 높은 배율과 고 해상도로 동물 장기조직 시료의 세부 구 조를 관찰할 수 있다. X-선 영상은 위상 대조도 메커니즘으로 설명할 수 있다. 우리는 쥐의 꼬리, 신경 및 허파 의 in-vivo 및 in-vitro위상 대조도 영상을 8 KeV mono 빔으로부터 10배 현미경대물렌즈와 CCD 카메라를 이용하여 얻었다. 기존의 흡수 X-선 영상 보다 SR 영상이 세밀한 구조의 높은 분해능 영상을 볼 수 있었다. SR 영상은 생물학, 재료 및 임상 연구에 무한한 가능성을 가지고 있다.

Officers and ratings as a group might show differences in some aspects of personality , human relations, job attitudes, perception of business environment and surrounding organizational structure. It has been traditionally believed that licenced-officers are required to have nicely-paired leadership and dignity , and ratings obedience in maritime field. This survey revealed that officers and ratings have some differences in the actual behavior, knowledge , understanding attitude etc., In summary , officers as a superstructure of merchant ship's orgnaization are different, to some degree, from ratings as an infrastructure in several aspects. Officers are believed to have the characteristics of maturity by taking concern of business environment , social circumstance away from the vessels which they are on board. In contrast, ratings are greatly interested in the surrounding environment associated with themselves, and also experiencing alienation and technology.

본 실험은 질소시용수준에 따른 수도절간의 조직구조에 미치는 영향과 품종간차이 및 조계구조와 수상특성과의 관련성을 구명코자 실시하였는바 다음과 같은 결과를 얻었다. 1. 각 절간의 대유관속수 및 크기는 질소무비구에 비하여 질소증시구에서 증가하였고, 특히 그 수는상위제 1절간에서, 크기는 상위제3·4·5절간에서 뚜렷한 차이를 나타냈다. 통일계품종은 일반계품종보다 대유관속수가 많았고. 크기가 컸다. 2. 통기강수는 질소를 증시함에 따라 질소무비구에 비하여 많았다. 상위제3·4절간에서 통기강수 및 크기의 품종간차이를 보였고, 특히 상위제 3절간에서 풍산벼와 추청벼는 통기공이 발달되었으나 유신과 진흥은 발달되지 않았다. 3. 대유관속수와 크기 및 절간굵기와 수상특성(수장, 1·2차지경 및 영화수)과는 밀접한 정의 상관을 나타냈다