We review recent systematic investigation of the X-ray spectra of early type galaxies by using the Einstein data base and present new results by the ROSAT observations. The Einstein data suggested that the galaxies with low X-ray to optical luminosity ratio may have another very soft component. ROSAT observations confirm its presence and call for further study to understand the nature of this very soft emission. The X-ray bright galaxies have emission temperature of ∼0.8keV ∼0.8keV and show radial gradients in the sense that X-ray emission is softer and more absorbed in the inner region.

We have systematically investigated the X-ray spectra of normal galaxies, by using the Imaging Proportional Counter (IPC) data in the Einstein data base. We employed the X-ray color-color plot as well as the standard model fitting method which requires higher signal to noise ratio. We discuss X-ray emission mechanisms in terms of their spectral properties and the signature of cooling flows which are most likely present in X-ray bright early type galaxies. On the average, fits to absorbed thermal spectra show that the X-ray emission temperature of spirals is higher than that of ellipticals. This is consistent with our understanding that accreting binaries are a major X-ray source in spirals, while extended gaseous halos are present in ellipticals. The emission temperature becomes lower with increasing X-ray to optical luminosity ratio in E and S0 galaxies. This result is what we would expect if the emission of X-ray faint early type galaxies consists of a large evolved stellar component, while the gaseous emission becomes dominant in X-ray brighter galaxies. We also find a cool, self-absorbed core in some early type galaxies, which directly indicates the presence of cooling flows in such galaxies.

We investigated the effects of Acorus gramineus water extract on the blood lipid levels in high fat diet-fed obese male mice. We divided thirty-five C57BL/6 mice into 5 groups: normal group, control group, and groups treated with Acorus gramineus water extract at concentrations of 20, 100, and 500 ㎎/㎏. We inoculated Acorus gramineus water extract per orally once a day for 6 weeks respectively. The results revealed that Acorus gramineus water extracts had positive effects on the total cholesterol, triglyceride, high-density lipoprotein cholesterol, and low-density lipoprotein cholesterol levels.

본 연구는 경쟁이 치열해지고 상품 주기가 짧아지는 소셜 네트워크 게임의 한계를 극복하고 자 게임 개발사가 채택한 크로스 프로모션 전략에 주목하여, 게임 몰입에 미치는 영향에 대해 알아보았다. 연구결과, 게임을 적게 할수록 오락성, 자기표현 요인이 게임 몰입에 영향을 주는 반면, 게임을 많이 할수록 자기표현과 경쟁심리가 게임 몰입에 영향을 주는 것으로 나타났다. 또한, 게임 이용수준과 프로모션 이용 수준에 따라 프로모션에 대한 유용성과 성가심에 대한 인식이 차이가 있는데, 게임을 많이 하고 프로모션을 많이 이용할수록 프로모션의 유용성을 더 많이 인식하고 몰입도가 커지는 것으로 나타났다.

For the mass production of plug seedlings in cultivar ‘Dejima’ potato (Solanum tuberosum L.) the optimal apical cutting diameter for rooting and rapid multiplication of stem cuttings in hydroponics were determined. In addition, the best planting date was predicted to increase tuber yield of plug seedlings at fall cropping in Cheju-Do, Korea. Days to initial rooting decreased as the cutting diameter was reduced. Plant height, leaf number, root length and root weight per plant were favorable as the cutting diameter was small. The ideal cutting diameter was 1-2 mm in this experiment. In the hydroponic cultures, the Japanese standard (JS) nutrient solution was the most effective for multiplication of stem cuttings. It was able to propagate more than 20 times a month from a single mother plant. Viability of plants, which were derived from plug seedlings using stem cuttings, was excellent when transplanted to the field. The number of tubers and tuber yield in both of the plug seedlings and seed potato planting plots were high when planted on 25 August. The number and yield were reduced when planted on 15 August, 5 September and 15 September. The degree of decrease of tuber yield in the plug seedling planting plot however, was lower than that of seed potatoes when the planting date was late. In the case of small tubers (under 30 g), the number of tubers and tuber yield were evidently increased in the seed potato tuber planting plot; the yield of large tuber (over 80g) in the plug seedling planting plot was higher than that of the seed potato. The total tuber yield per plant in the plug seedling planting plot was less than that of the seed potato; therefore, in order to increase tuber yield it was necessary to increase field plant density.