Complicated crown-root fractures are considered rare occurrences in young permanent dentition; however, they often present complicated and unpredictable treatment options. The most common treatment option for crown-root fractured teeth is reattachment of fractured segment, but if it is thought impossible to maintain, it should be extracted. However, when unfavorable crown-root fracture occurs in the adolescents, extraction of fractured teeth is expected to be poor due to excessive resorption of alveolar and prosthetic replacement cannot be performed immediately, various treatment options should be considered. This report suggests root submergence in the complex crown-root fracture in growing patients is performed and the functional and aesthetic results including preservation of the alveolar bone are obtained.

본 연구에서는 직선 개수로 내 설치된 50% 잠긴 수제 모형 주위에서 발생하는 3차원 흐름 현상 연구를 위한 수리모형실험이 수행되었다. 수리모형실험은 두 가지 Froude 수(Fr≃0.10와 Fr≃0.18)에서 수행되었다. 그리고 본 실험 결과를 잠기지 않은 수제 실험결과(Jeon and Kang, 2016)와 비교하여 수제의 잠김 흐름 발생에 따른 흐름 변화를 관찰하였다. 시간평균유속과 난류에너지를 구하기 위해 초음파 유속계를 이용해 3차원 실시간 유속을 측정하였고 시간평균 수위를 측정하기 위해 초음파 거리 센서를 이용해 실시간 수위를 측정하였다. 수제의 잠김 흐름 발생은 3차원 유속분포에 큰 영향을 미치는 것으로 나타났다.

Anaerobic germination (AG) is plays important role in submergence resistance which is an important trait for rice production in flood-prone lowland areas. Slow seed germination and delayed seedling establishment due to flooding become major problem for modern sowing methods such as direct seeding and environmental friendly good agricultural practices especially using young seedling age. In total, 137 diverse rice accessions were evaluated for anerobic germination ability. Submergence 1 (SUB1) which is induced ethylene response factors is suggestive because genes belonging to this gene family play a crucial role in rice tolerance to submergence. In this study, haplotype variations of three AG related genes, SUB1 (SUB1A, SUB1B, SUB1C) were examined using whole-genome resequencing data of 137 accessions of rice core set. The new SNPs and InDels found in the exon of the sub1 loci would be useful in developing markers to screen the varieties with strong anaerobic germination ability in the future molecular breeding

This study is to identify the physiological traits of submergence-tolerant varieties of rice plants (Oryza sativa L.) in Yeongnam area, southeastern part of Korea, where the reduction of rice yield due to submergence is remarkably severe. In the present study, two tolerant varieties of rice plants were selected from over 30 rice varieties grown in under a 10-day period. The tolerant varieties selected from a submerged paddy field. As a control, one intolerant variety of rice plant was chosen. Of the tolerant variety Samgangbyeo, rather than Haepyungbyeo, had a lower dissolved oxygen consumption and maintained a higher dry weight than the intolerant variety. The leaf photosynthetic rates (LPS) of the two tolerant varieties were significantly higher than that of the intolerant-variety after four days of submergence treatment. These results indicate that lower dissolved oxygen consumption in a limited pool is prevented by ethylene formation in the tolerant varieties, which may be a mechanism of submergence tolerance.

이 연구에서는 벼 생육기 침수에서 피해가 가장 뚜렷이 나타나는 주요생육형질의 품종간 차이와 벼의 생식생장기 침수에서 피해를 크게 좌우하는 임실장해의 정도가 가장 예민하게 나타나는 시점을 찾기 위하여 벼의 포기단위, 이삭단위, 그리고 영화단위로 청수와 탁수로 처리하여 얻어진 결과를 요약하면 다음과 같다. 1. 침수일수의 증가에 따라 엽초의 이상신장량이 많아졌고, 침수후의 초장신장량 및 분벽수는 감소되었으며 출수지연일수가 길어졌다. 2. 일/인형 품종은 일본형 품종에 비하여 엽초의 이상신장량이 적고 침수후 초장 신장의 억제 및 분벽력의 감소가 적었다. 3. 침수에 의한 임실장해가 가장 심한 시기는 청수와 탁수 모두 출수기이었으며 특히 출수전의 수잉기말에서 출수후 개화하기 전이었다.