• Tuberculosis and Respiratory Diseases
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• v.56 no.5
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• pp.514-522
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• 2004

Background : Non-steroidal anti-inflammatory drugs (NSAID) are useful in chemoprevention of colorectal cancers. Continuous NSAID administation causes 40% to 50% reduction in relative risk for colorectal cancer. Sulindac possesses an antiproliferative effect and induces apoptosis and tumor regression on colon cancer and other types of cancers. We intended to analyze the effects of sulindac in three non-small cell lung cancer cell lines. Materials and Methods : The human lung cancer cell lines, A549, NCI-H157 and NCI-H460 were used for this study. Viability was tested by MTT assay, and cell death rate was measured by lactate dehydrogenase(LDH) release. Apoptosis was estimated by flow cytometric analysis and nuclear staining. Results: Sulindac was able to decrease the viability of non-small cell lung cancer cells in a dose- and time- dependent manner. In a parallel effect of sulindac on cell death rate, LDH release was increased in sulindac-treated lung cancer cells. Sulindac significantly increased apoptosis characterized by an increase of $sub-G_0/G_1$ fraction and morphological change of nuclei. The rate of apoptotic cells after sulindac treatment in lung cancer cells increased in a time- and dose- dependent manner in flow cytometric analysis. Apoptotic cells were defined as nuclear shrinkage, chromatin condensation and nuclear fragmentation of cells. Conclusion : Sulindac decreases viability and induces the apoptosis of lung cancer cells. Further studies will be needed to elucidate the potential mechanism of sulindac-induced apoptosis in lung cancer cells.

• Korean Journal of Environment and Ecology
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• v.34 no.1
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• pp.42-54
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• 2020

This study aimed to analyze the rate of increase and spread patterns of dead trees of the conifer (Abies koreana and others) in subalpine zones by using the high-resolution aerial images in Jirisan National Park around 10 years ago. Furthermore, factors affecting the death of conifer were identified by analyzing the altitude, topographical information, solar radiation, and moisture environment of the site where the dead trees are located. The number of dead trees per unit area increased by two to five times in the Banyabong peak, Yeongsinbong peak, and Cheonwangbong peak in Jirisan National Park over the past decade. The increase was about 2 times in the Banyabong peak, about 3.9 times in the Yeongsinbong peak, and about 5.2 times in the Cheonwangbong peak, indicating the most notable increase in the Cheonwangbong peak. It is estimated that dead trees commonly occurred in the environments where the soil moisture content was low due to the high slope, amount of evaporation was high due to strong solar radiation as the location faced south, and the soil was dry due to strong solar radiation and short rain retention time. In other words, dead conifer trees in subalpine zones were concentrated in dry location environments, and the tendency was the same more than ten years ago.

• Research in Plant Disease
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• v.23 no.1
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• pp.49-55
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• 2017

The previous study showed that die-back of apple trees caused by soil-borne diseases was significantly high in the apple orchards in Chungbuk province. The correlation between dieback ratio and cultivation environment in apple orchards infected by soil-borne diseases was investigated in this study. The dieback ratio of five orchards diseased by violet root rot and five places infected by white root rot showed significantly positive correlation with Ca content and available $P_2O_5$ content in soil, respectively. Whereas, the dieback ratio of fourteen orchards diseased by Phytophthora root rot was not significant. Subgrouping of cultivation environment analysis showed that the slope degree of orchard and the number of fruit setting also affected the dieback ratio caused by violet root rot and Ca content in soil also affected the dieback ratio caused by white root rot. It showed that the slope degree, soil texture, Mg and Ca content affected the dieback ratio caused by Phytophthora root rot. These results can be applied to reduce die-back ratio by the modification cultivation environment for each soil-borne disease.

• Korean Journal of Clinical Laboratory Science
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• v.48 no.2
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• pp.102-108
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• 2016

Der p 2 is the major allergen of the house dust mite (HDM) associated with the development of allergic diseases. The pathogenic mechanism of the allergy is related to cytokine release of lymphocytes and constitutive apoptosis of neutrophils. In the present study, we examined whether Der p 2 induces cytokine release of lymphocytes, which is involved in regulation of neutrophil apoptosis. In normal and allergic subjects, Der p 2 enhanced the secretion of IL-6, IL-8, MCP-1, and GM-CSF in a time-dependent manner. Although Der p 2 was weakly effective against neutrophil apoptosis, conditioned media collected from normal and allergic lymphocytes after Der p 2 treatment inhibited the apoptosis of normal and allergic neutrophils. Der p 2 showed stronger inhibition of apoptosis of allergic neutrophils cocultured with allergic lymphocytes than normal neutrophils cocultured with normal lymphocytes. These findings improve our understanding of the role of Der p 2 in regulation of lymphocytes and neutrophils and will enable elucidation of allergy pathogenesis.

• Proceedings of the Acoustical Society of Korea Conference
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• autumn
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• pp.279-282
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• 2001

해마다 실시되고 있는 대학수학능력시험의 듣기 평가시험에 있어서, 고사장 및 지점별 음향 성능에 기인한 레벨 편차와 명료도를 산출하여 학생 선발의 공공성과 객관성을 검토해 보고자 한다. 일반적으로 듣기 평가가 이루어지는 각 고사장은 듣기 평가 실시에 지장이 없는 고등학교 교실로 지정하고 있지만, 균등한 음 환경을 제공해야 하는 시험의 성격에 반해 학교 자체의 방송 시설을 그대로 사용하는 것은 평가의 형평성 및 객관성에 충실하지 못하게 되는 요인이 된다. 따라서, 각 고사장의 확성 시스템에 따른 음성 전달품질과 수험생간의 좌석별 음압 레벨 및 명료도를 평가하였고, 실험 결과 RASTI를 비롯한 음성 및 음절 명료도를 나타내는 파라메터에서 좌석별로 큰 편차가 있는 것으로 분석되었다.

• Korean Journal of Environment and Ecology
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• v.13 no.3
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• pp.280-287
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• 1999

본 연구는 우리나라 특산식물인 히어리 군락이 지리산 국립공원 동부지역에 대규모로 분포하고 있는 것을 처음으로 발견하여 군락지의 분포 및 맹아지 특성 그리고 군락의 보호대책을 위한 기초자료를 축적하고자 수행되었다. 각 계층별 중요치는 교목층에서 소나무(134.15) 일본잎갈나무, 산벚나무, 비목나무, 신갈나무 등이 우점하였고 아교목층에서는 히어리, 거제수나무. 비목나무, 졸참나무, 노각 나무 그리고 관목층에서는 히어리가 우점하였으며 그 외에 철쭉꽃, 진달래, 생강나무 등이 출현하였다 그리고 맹아지 특성은 1개 방형구(25m2)에 평균 17.75개의 주간이 형성되고 1개 주간당 맹아지 수는 평균 6.00개 고사지는 2.80개로 조사되었다. 흉고직경급별 분포에서 생장지의 경우 흉고직경 1.0-4.0cm 구간에서 전체의 64.78%를 차지하였으며 대부분 2.0-3.0cm 구간에서 54.74%를 차지하여 히어리 군락의 중심계급이었다 흉고직경 1.0cm 이하의 고사지가 전체의 53.16%를 차지하였는데 이는 근주에서 돋아나는 1년생 맹아지가 대부분 고사하였기 때문이었다 특히 히어리의 번식습성은 실생묘에 의한 번식도 가능하지만 본 조사지에서와 같이 수관이 울폐된 지역에서는 주로 근맹아에 의한 번식을 더 선호하는 것으로 나타났다.

• Korean Journal of Environment and Ecology
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• v.14 no.1
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• pp.80-87
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• 2000

구상나무림 보전관리의 기초자료를 마련하고자 지리산 한라산 및 덕유산의 아고산지대에 95개의 조사구를 설치하여 한국특산종 구상나무의 생육현황과 구상나무 서식지의 입지인지를 조사하였다 구상나무는 흉고직경 10-30cm의 범위에 드는 나무들이 주로 고사목으로 나타났으며 고사목의 비율은 전체적으로 총개체수의 11.51%였다 고사목의 비율또한 덕유산에서 18.18%로 가장높게나타났고 한라산 지역이 8.11%로 가장 낮게 나타났다 조사구당 구상나무 개체수 치수의 개체수 구상나무의 수고와 흉고직경 생육현황표에 의한 점수 구상나무의 상대밀도 등은 지역간에 통계적 유의차가 인정되었다 생육중인 구상나무의 활력은 한라산 지리산, 덕유산으로 순으로 좋았다 조사구당 구상나무 치수의 개체수는 한라산에서 6.00개체로 가장 많았으며 덕유산에서는 치수가 없는 것으로 나타났다 구상나무의 상대밀도도 한라산, 지리산, 덕유산 순으로 높게 나타났다. 조사구당 구상나무 개체수는 해발고와 정의 상관, 방위, 낙엽퇴의 두께, 조사구당 교목의 개체수 및 종수, 활엽수 상대밀도와는 부의 상관이 인정되었다. 구상나무 상대밀도는 해발고와는 고도의 정의 상관관계 방위 조사 구당교목의 개체수 및 종수 수관울폐도, 활엽수 상대밀도와는 부의 상관관계가 인정되었다 지리산, 한라산 및 덕유산에 자생하는 구상나무는 해발고가 높으며 볕이 잘들고 낙엽퇴가 얕으며 종구성이 단순하고 활엽수가 적은 지역에 보다 많이 분포한다.

• Korean Journal of Medicinal Crop Science
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• v.4 no.3
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• pp.236-240
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• 1996

1. The pathogenic fungi which infect to shoot of peony was 7 species. The infected parts were as followed, leaf spot disease was in leaf, leaf blotch was stem, powdery mildew was whole aeri­al part of both leaf and stem. 2. The major diseases were leaf spot and powdery mildew, and begin to occur from late April to mid­dle May, and then rapidly heavy infected. The 'Euiseongpeony' variety was more susceptible to those diseases than the 'Yeongcheonpeony' variety. 3. The blight of top part by seasonal in 1995 was begun at late May and increased rapidly 50.6% in Early August.

• Journal of Korean Ophthalmic Optics Society
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• v.4 no.1
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• pp.1-6
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• 1999

The corneal epithelium is constantly shed and apoptosis may play an important role in this turn-over. We sought to define that serum-free medium was able to induce apoptosis of corneal epithelial cells. SV-40 transfected human corneal epithelial(HCE) cells were grown to 70% confluency in culture. Serum-free medium was added to cells and the cells incubated for 1, 2, 3, or 6 days. Apoptosis of cells at different times was assessed by staining cells with Giemsa or Hoechst 33342 and measuring DNA fragmentation using the TUNEL assay. HCE cells exposed to serum-free medium demonstrated a high incidence of apoptosis, which increased over time to $50{\pm}4%$ after 3 days. They also stained positively with TUNEL assay. Serum-free medium caused time dependent apoptosis of HCE cells. Thus, serum-like nutrient might be important in corneal epithelial cell homeostasis.

• Journal of the Korean Chemical Society
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• v.64 no.3
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• pp.189-195
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• 2020

In the study, the effect of flipped classroom approach applied to chemistry I class in a foreign language high school was explored. Flipped classroom was applied to 176 grade 10 students (43 boys and 133 girls) from a foreign language high school located in a metropolitan city for one semester and its instructional effects were studied in terms of cognitive and affective aspects. Before the class, students were provided with guiding worksheets and asked to summarize contents. Within the class, various student-centered activities were adopted. After the flipped classroom for one semester, mid-term and final-term exam scores were analyzed, and students' attitude toward chemistry class and flipped classroom were surveyed. Analysis on the exam scores showed the possibility for positive impact on students' achievement and perceptions on chemistry class including flipped classroom approach. Moreover, some students mentioned flipped classroom was helpful for self-directed learning and meta-cognition. Based on these results, educational implications were discussed.