• Journal of The Korean Association For Science Education
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• v.33 no.7
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• pp.1285-1299
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• 2013

Nurturing students' scientific creativity is considered an important element in science education in Korea. The study aims to explore patterns displayed by well-known scientists in their quest for problem finding. Each case of scientists' course of problem solving is described in terms of historical background, a process of problem finding, and a process of problem solving. There are five patterns from ten scientists which are as follows: Pattern 1 is that scientists find problems from insufficiencies and/or errors from explanation of theories at the time and the related cases are A. Lavoisier, G. Mendel, and J. Watson. Pattern 2 shows that scientists find a problem because of strange phenomena unexplained by theories at the time, and here important case studies are E. Rutherford and W. R$\ddot{o}$ntgen. Pattern 3 demonstrates that scientists find a problem from analogical reasoning between known theories and unknown science phenomena. The cases include S. Carnot and T. Young. Pattern 4 points to the fact that scientists find a problem while they utilize a newly invented experimental instrument. Here, G. Galilei is an important example. Pattern 5 establishes that scientists happen to find a problem while they conduct research projects. The works of M. Faraday and J. Kepler are prominent case studies related to this pattern.

• Radiation Oncology Journal
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• v.24 no.4
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• pp.243-247
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• 2006

$\underline{Purpose}$: To evaluate the treatment results and prognostic factors of palliative radiation therapy in the patients with unresectable advanced pancreatic cancer. $\underline{Materials\;&\;Methods$: Thirty-seven evaluable patients with unresectable advanced pancreatic cancer who were treated by palliative radiation therapy for pain relief at the Department of Radiation Oncology, Kangnam St. Mary's hospital, the Catholic University of Korea between March 1984 and February 2005 were analysed retrospectively. There were 22 men and 15 women. Age at diagnosis ranged from 30 to 80 (median 57) years. Twelve patients (32.4%) had liver metastases and 22 patients (59.5%) had lymph node metastases. Radiation therapy was delivered to primary tumor and regional lymph nodes with $1{\sim}2\;cm$ margin, and total dose was $3,240{\sim}5,580\;cGy$ (median 5,040 cGy). Chemotherapy with radiotherapy was delivered in 30 patients (81%) with 5-FU alone (21 patients) or gemcitabine (9 patients). The follow-up period ranged from 1 to 44 months. Survival and prognostic factors were analysed using Kaplan-Meier method and log-rank test respectively. $\underline{Results}$: Overall mean and median survival were 11 and 8 months and 1-year survival rate was 20%. Among 33 patients who were amenable for response evaluation, 7 patients had good response and 22 patients had fair response with overall response rate of 87.9%. Mild to moderate toxicity were observed in 14 patients with nausea, vomiting, and indigestion, but severe toxicity requiring interruption of treatment were not observed. Chemotherapy didn't influence the survival and symptomatic palliation, but the group containing gemcitabine showed a tendency of longer survival (median 12 months) than 5-FU alone group (median 5.5 months) without statistical significance (p>0.05). The significant prognostic factors were Karnofsky performance status and liver metastasis (p<0.05). Age, sex, tumor location, lymph node metastasis, and CA 19-9 level did not show any prognostic significance (p>0.05). $\underline{Conclusion}$: Radiation therapy was effective for symptomatic palliation in the patients with unresectable advanced pancreatic cancer and would play an important part in the survival benefit with gemcitabine or other targeted agents.

• Journal of Food Hygiene and Safety
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• v.24 no.4
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• pp.391-397
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• 2009

Carnosine is a dipeptide ($\beta$-alanyl-L-histidine) found in mammalian brain, eye, olfactory bulb and skeletal muscle at high concentrations. Its biological functions include antioxidant and anti-glycation activities. The objectives of this study were to investigate anti-diabetic effects of carnosine as determined by blood glucose levels in glucose tolerance test (GTT) and insulin tolerance test (ITT), insulin level and serum biochemical and lipid levels in male C57BL/6J db/db mice. There were five experimental groups including normal (C57BL/6J), control (vehicle), and three groups of carnosine at doses of 6, 30, and 150 mg/kg b.w. Carnosine was orally administered to the diabetic mice everyday for 8 weeks. There was no significant difference in body weight changes in carnosine-treated groups compared to the control. The treatments of carnosine significantly decreased the blood glucose level in the diabetic mice compared with the control (p < 0.05) after 5 weeks. The treatments of carnosine also significantly decreased the blood glucose levels in GTT and ITT and glycosylated hemoglobin (HbA1c), compared with the control (p < 0.05). Carnosine at the dose of 6 mg/kg significantly decreased the serum insulin level compared to the control (p < 0.05). Carnosine significantly increased total proteins but significantly decreased lactate dehydrogenase and blood urea nitrogen compared with the control (p < 0.05). Carnosine also significantly decreased glucose, LDL, and triglyceride in the serum of diabetic mice compared to the control (p < 0.05). These results suggest that carnosine has a hypoglycermic effect resulting from reduction of glucose and lipid levels and that high carnosine-containing diets or drugs may give a benefit for controlling diabetes mellitus in humans.

• Radiation Oncology Journal
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• v.20 no.4
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• pp.323-327
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• 2002

Purpose : To evaluate the outcome of early stage non-small cell lung cancer patients who were treated with radiation therapy alone and define the optimal radiotherapeutic regimen for these patients. Materials and Methods : A retrospective review was peformed on patients with sage I or II non-small cell carcinoma of the lung that were treated at our institution between June, 1987 and May, 2000. A total of 21 patients treated definitively with radiation therapy alone were included in this study. The age of the patients ranged from 53 to 81 years with a median of 66 years. All the patients were male. The medical reasons for inoperability were lack of pulmonary reserve, cardiovascular disease, poor performance status, old age, and patient refusal in the decreasing order. Pathological evidence was not adequate to characterize the non-small cell subtype in two patients. Of the remaining 19 patients, 16 had squamous cell carcinoma and 3 had adenocarcinoma. Treatment was given with conventional fractionation, once a day, five times a week. The doses to the primary site ranged from 56 Gy to 59 Gy. No patients were lost to follow-up. Results : The overall survival rates for the entire group at 2, 3 and 5 years were 41, 30 and $21\%$, respectively. The cause specific survivals at 2, 3 and 5 years were 55, 36 and $25\%$, respectively. An intercurrent disease was the cause of death in two patients. The cumulative local failure rate at 5 years was $43\%$. Nine of the 21 patients had treatment failures after the curative radiotherapy was attempted. Local recurrences as the first site of failure were documented in 7 patients. Therefore, local failure alone represented $78\%$ of the total failures. Those patients whose tumor sizes were less than 4 cm had a significantly better 5 year disease free survival than those with tumors greater than 4 cm $(0\%\;vs\;36\%)$. Those patients with a Karnofsky performance status less than 70 did not differ significantly with respect to actuarial survival when compared to those with a status greater than 70 $(25\%\;vs\;26\%,\;p>0.05)$. Conclusion : Radiation therapy 리one is an effective and safe treatment for early stage non-small ceil lung cancer patients who are medically inoperable or refuse surgery. Also we believe that a higher radiation dose to the primary site could improve the local control rate, and ultimately the overall survival rate.