• Journal of Life Science
• /
• v.18 no.8
• /
• pp.1042-1048
• /
• 2008

Prostate cancer is the most predominant cancer in men and related death rate increases every year. Till date, there is no effective therapy for androgen independent prostate cancer. To investigate the mechanism for cell growth inhibition or apoptosis in human androgen independent prostate cancer PC-3 cells after gamma irradiation. The aim of this study was to examine the potential of gamma irradiation to induce apoptosis in PC-3 cells and to assess the mechanism of gamma irradiation-induced apoptosis. Five different assays were employed in this study: cell proliferation assay, morphological assessments of apoptotic cells, DNA fragmentation analysis, quantification of apoptosis by annexin V (AV) and propidium iodide (PI) staning, and western blot analysis. Cell viability was inversely related to radiation dose. DAPI-positive cells were detected 48 hr after 40 Gy radiation exposure. And nuclear morphological changes of cells were observed by gamma irradiation. DNA ladder patterns in the cells exposed to gamma-radiation were appeared at 24 hr. Also, gamma irradiation induces apoptosis of PC-3 cells via Caspase3, Bax and PARP-dependent fashion.

• Journal of the Economic Geographical Society of Korea
• /
• v.3 no.2
• /
• pp.43-61
• /
• 2000

This study investigate the spatial characteristics and corporate networks of foreign business service firms in Korea. Specifically intrafirm and extrafirm organization of foreign firms are addressed utilizing the corporate network perspective. For this purpose, this study conducted questionnaire and interview surveys for the foreign firms. Parent-subsidiary relationships are focused on the mechanisms by which Transnational Corporations (TNCs) headquarters control and coordinate their foreign affiliates and subsidiaries in order to achieve investment purpose in Korea (overseas market expansion). But extrafirm networks of foreign business services firms in Korea do not appear to play an important role in regional development to date. A low proportion of foreign firms is engaged in academics-industry linkages, and a low number o( foreign firms is formally linked with government organizations, research institutes, and trade associations. To conclude, Foreign direct investment firms in business services in Korea are characteristics by globalized intrafirm networks and localized interfirm and extrafirm networks. It is understood that regional development can be vitalized when Korean local firms have close relationships with technologically advanced foreign firms in tacit knowledge capacity. Foreign firms are able to play an important role in the development of business services in Korea. This study suggests that regional foreign direct investment policy should be targeted towards the corporate networking with foreign firms and domestic firms and incrementation of the potential of foreign firms as a knowledge-intensive industry.

• Proceedings of the Korean Magnestics Society Conference
• /
• 2006.06a
• /
• pp.146-147
• /
• 2006

• Journal of Korean Electronics
• /
• v.10 no.6
• /
• pp.42-49
• /
• 1990

전자산업의 급속한 성장에 따라 수정응용산업도 지속적인 성장을 해왔으나 기술적인 측면에서 균형적인 발전이 이루어지지 않아 부품기술 수준이 완제품 개발을 뒷바침 하지 못나는 실정으로서 사실상 기술집약형 고부가가치 제품은 수입에 의존하고 저부가가치 제품을 국내 생산을 통해 해외로 수출하고 있는 상황이다.

• Proceedings of the Optical Society of Korea Conference
• /
• 2005.07a
• /
• pp.92-93
• /
• 2005

• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
• /
• 2003.08a
• /
• pp.44-52
• /
• 2003

항만 및 해안의 이용과 개발 그리고 연안해역공간에서 발생하는 각종 재해를 예방하는 측면에서 볼 때 해안에서 형성되는 여러 물리적인 현상들을 정확하게 이해하고 해석하여 필요에 따라 적절히 활용할 수 있는 것이 무엇보다도 중요한 과제이다. (중략)

• Proceedings of the Korean Magnestics Society Conference
• /
• 2001.04a
• /
• pp.130-131
• /
• 2001

• Korean Journal of Pharmacognosy
• /
• v.34 no.1 s.132
• /
• pp.75-79
• /
• 2003

Hypoglycemic activity of Opuntia ficus-indica var. sabotan on alloxan or streptozotocin-induced diabetic mice was investigated. Fructus and folium of Opuntia ficus-indica vars. sabotan inhibited intestinal ${\alpha}-glucosidase$ of rats as well as glucose elevation in blood of normal mice, Opuntia ficus-indica var. sabotan exhibited inhibitory activities on streptozotocin-induced diabetic mice rather than on alloxan-induced diabetic mice loaded with maltose and sucrose. Its folium was more effective than its fructus. These results suggest that Opuntia ficus-indica var. sabotan might be effective on diabetic mellitus.

• Journal of the Korean Chemical Society
• /
• v.31 no.3
• /
• pp.225-230
• /
• 1987

Electrical conductivity of $CdO-La_2O_3$ system containing 0.8mol% of CdO was measured from 500 to $900^{\circ}C$ at oxygen partial pressures of $10^{-7}\;to\;10^{-1}$ atm. Plots of log ${\sigma}$ vs. 1/T at constant $PO_2$ are found to be linear and the activation energy appears to be 0.97eV. The log ${\sigma}$vs. log $PO_2$ is found to be linear at oxygen pressures of $10^{-7}\;to\;10^{-1}$ atm and $500{\sim}900^{\circ}C$. The conductivity dependence on $PO_2$ at the above temperature range is given by ${\sigma}\;{\alpha}\;PO_2^{1/4}$. The defect structure in this system is believed to be complex, i.e., ${V_{La}}^{'''}$ and $V\"{o}$. The interpretations of conductivity dependences on temperature and $PO_2$ are presented and conduction mechanism is proposed to explain the data.

• Journal of Environmental Policy
• /
• v.6 no.1
• /
• pp.83-109
• /
• 2007

This study evaluates citizen's willingness-to-pay for the benefits from improved water quality of the Taehwa river in Ulsan, Korea, using a contingent valuation method with double-bounded dichotomous choice. The estimation results of the bivariate probit model shows the amounts of willingness-to-pay are monthly 3,458.5 Korean Won per household and yearly 14,760 million Korean Won for total households in Ulsan, Korea. These estimates are equivalent to the social values of improved water quality of the Taehwa river. This study also tests the inter-dependence between two answers, which may occur in the responses of the questions for the double-bounded dichotomous choice, and all the null hypotheses on the inter-dependence are rejected in this study.