동해안 산불과 기상

임주훈 한국농림기상학회 2000 한국농림기상학회지 Vol.2 No.2

간헐적 교정력 적용 후 백서 치주인대에서 UNC-50 유전자의 발현

박미경,박주철,임성훈,김광원 대한치과교정학회 2006 대한치과교정학회지 Vol.36 No.4

기계적 응력은 정상적인 발달과정 동안 조직의 항상성에 있어 중요한 역할을 한다. 기계적 응력은 치아 이동과 저작과 같은 상황을 포함한다. 치아 이동과 저작 중에 치주인대 섬유모세포는 기계적 자극을 감지하고 주위의 세포밖 물질과 생체분자 대사의 변동에 의해 반응을 보인다. 그러나 아직까지 기계적 응력 하에서 치주인대 세포에서 발현된 유전자에 관한 연구는 미비한 실정이다. 최근 기계적 응력이 초파리에 존재하는 UNC-50 유전자에 영향을 줄 수 있다고 보고되었다. 또한 UNC-50은 치은 섬유모세포와 비교해 치주인대 섬유모세포에서만 발현된다고 보고되었다. 본 연구에서는 간헐적 교정력 적용 시에 백서의 치아에서 일어나는 치근 및 치주 조직의 조직학적 변화와, UNC-50의 발현 양상을 면역조직학적 염색으로 조사하여 치주인대에서 기계적 응력과 UNC-50의 관련성을 알아보고자 하였다. Sprague-Dawely계 수컷 백서 12마리를 4마리씩 세 군으로 나누어 상악 우측 구치부에 NiTi closed coil spring을 사용하여 40 g 정도의 견인력이 발생하도록 하여 하루에 1시간씩 간헐적인 교정력을 적용한 후 1, 3, 5일 후 치주인대의 조직학적 변화를 관찰하여 다음과 같은 결과를 얻었다. 조직학적 소견에서 상악 제1대구치 근심구개치근의 치근부 1/3에서 압박측은 안장측보다 더 좁은 치주인대공간을 보였고 교정력을 적용시킨 후 3일 후부터 인장측에서 백악모세포 활성으로 인한 백악질 침착이 관찰되었다. UNC-50은 인장측의 분화 중인 백악모세포에서 강한 발현을 보였다. Osteocalcin은 인장측에서 압박측에 비해 신생 백악질에 존재하는 분화 중인 백악모세포를 따라 강한 발현을 보였다. 이상의 연구결과는 UNC-50이 간헐적 교정력 즉 기계적 응력의 변화에 따른 백악모세포의 분화과정에 중요한 역할을 함을 나타낸다. 그러나 이를 명확히 하기 위해서는 교정력 적용 후 UNC-50의 세포내 신호전달과정에 대한 보완연구가 필요할 것이다. Objective: Periodontal ligament fibroblasts have an ectomesenchymal origin and are thought to play a crucial role for not only homeostasis of periodontal tissues but also bone remodeling, wound healing and regeneration of tissues. Recently, it has been reported that UNC-50 is not expressed in gingival fibroblasts but in PDL fibroblasts. The purpose of this study was to examine the expression of UNC-50 and osteocalcin in the periodontium after application of intermittent force. Methods: Twelve rats had 40 grams of mesially-directed force applied at the upper molar for 1 hour/day. Four rats were sacrificed at 1, 3 and 5 days. Immunohistochemical localization of UNC-50 and osteocalcin antibody was carried out. The results showed apposition of new cellular cementum and a slight increase in periodontal space at the tension side. Results: Strong UNC-50 expression was observed in the differentiating cementoblasts close to PDL fibroblasts in the tension side whereas it was barely expressed at the compression side. Expression was strong at day 3, and decreased at day 5. Osteocalcin immunoreactivity expression was strong in differentiating cementoblasts at the tension side. Conclusion: It can be suggested that UNC-50 is related to the differentiation of cementoblasts, and may be responsible for the molecular event in PDL cells under mechanical stress.

Wildfires on the East Coast and Restoration of Plant Life

Lim Joo-hoon Researcher, Korea Forest Research Institute The Korea Foundation 2000 Koreana (English) Vol.14 No.4

Studies on the Ecological Characteristics of Natural Stands in Pinus koraiensis

Joo Hoon Lim 한국산림과학회 1991 한국산림과학회지 Vol.80 No.1

In order to find out the ecological niche of Pinus koraiensis distributed naturally in South-Korea, twelve natural stands and five artificial stands were selected and surveyed. The environmental elements of climate, soil and vegetation were surveyed and analyzed. Besides tree morphological characteristics, the morphological and anatemical traits of the two-year-old needles were quantitatively measured. Using these data, statistical analyses were performed such as ANOVA test, Duncan`s multiple range test, hierarchical analysis of variance(NESTED) factor analysis and cluster analysis, Meanwhile, at `Kwonkeumseong` in Mt. Seorak, the height- and age-class structure of Pinus koraiensis population was analyzed. The analysis of the whole data provided the following` information and results. During this survey, three new natural stands of Pinus kozaiensis were discovered for the first time at Mt . Odae, Mt. Kaya and Yangsan (Table 1). 1. In most natural stands except `Kwonkeumseong`, individual trees of Pinus kozaiensis were sub - dominant and randomly dispersed (Table 2, Fig. 3). 2. In the natural stands, the overstory dominant species were mostly Qtrercus mongolica or Qrrercus serrata and infrequently Abies holophylla (Table 2). And Acer pseudo-sieboldianum, Quercus mongolica and Tilia amurensis var. barbigera were dominant sub-overstory. Rhododendron mucrorarlatum, Rhudodendron sehlippenbuclrii, Rhudodendrun yedoense var. pouklzunense and Lesprdeza bicolor dominated in shrub layer and Festuca ouina in herb layer (Table 4) . 3. Sorensen`s similarity indices of both stories(overstory and understory) were higher between closely located stands. 4. Most stands had Brown forest soil but the soil of the stand at `Yangsan` was classified as Lithosol and that of `Hongcheongun` was Dark red brown forest soil. The general soil depth was SU-90㎝ and the depth of A layer was about 16㎝ (Table 6). 5. According to the climate-diagram, the annual precipitation is sufficient for all stands, but the water-balance diagram displayed a general tendency of water deficit around a year, except summer season, because of large evaporation (Fig. 4). 6. The height-and age class structure of the Pinus koraiensis population at `Kwonkeumseong` drew an inversed J-shaped curvey(Fig. 5,6). 7. ANOVA tests were performed for the tree morphological characteristics such as height, clear bole length, DBH, longest crown width, shortest crown width, upwind branch length, downwind branch length, length of the Longest branch, thickness of the longest branch, ramification from bole nodes, ramification from the longest branch, height of Stem split, length of dead stemtop, age and branch angle (Table 8). Most of these traits showed very statistically significant differences among stands. But the length of dead stemtop was not significant (Tiable 9). 8. Except for the needle width and needle thickness, the AVOVA tests of the morphological and anatomical needle traits, such as needle length, stomata number, stomatal row number, endodermical cell number, the number of resin ducts in middle region, the number of serrations on abaxial side, and resin duct index, showed significant differences among stands and among individual trees within each stand (Table 10, 11, Fig. 8). 9. The relationship among the correlated variables 38 variables: were supported by principal component analysis and factor analysis. $quot;Che results based on the analysis of all stands showed that 9 factors could be presented for interpretation (Table 12, Fig. 9). a). The first factor accounted for 18? of the total variation with eigenvalue 6.23 was largely composed of tree morphological characteristics, such as ramification from bole nodes, the largest crown width, upwind branch length, ramification from the longest branch, branch angle, age and altitude, b) The second with eigenvalues 4.96 and proportion 14%, was made up of needle characteristics, such as endodermical cell number, stomatal row n

Comparison of Mechanical and Enzymatic Methods for the Isolation of Bovine Ovarian Follicles

Lim, Hyun-Joo,Kim, Dong-Hoon,Im, Gi-Sun,Lim, Jeong-Mook 韓國受精卵移植學會 2010 한국동물생명공학회지 Vol.25 No.2

The isolation of preantral follicles from the ovaries of bovine was performed under mechanical and enzymatic methods. A significant increase in the total number of follicles retrieved was detected when tissue chopper was used. Micro-dissection could supply good quality, larger sized follicles (400 to ) but with the lowest yield (). The isolated preantral and early antral follicles were cultured for 14 days. Follicles isolated by the mechanical method had a greater growth during a culture period than follicles collected enzymatically. Morphologically normal bovine oocytes from early antral follicles after 14 days culture were 59.6% after culture and after 24 h of maturation culture, 12.9% of in vitro-grown oocytes reached the second metaphase. In conclusion, this study showed that mechanical method can be used effectively to isolate intact preantral follicles from bovine ovaries.

Method of recovery on isolation of preantral follicles from bovine ovaries

Lim Hyun Joo,Dong-Hoon Kim,Seongsoo Hwang,Yeoung-Gyo Ko,Jeong-Mook Lim,Boh-Suk Yang,Hwan-Hoo Seong 한국동물생명공학회(구 한국동물번식학회) 2007 발생공학 국제심포지엄 및 학술대회 Vol.2007 No.1

In Vitro Growth of Bovine Preantral Follicle under Different Culture Conditions

Lim, Hyun-Joo,Kim, Dong-Hoon,Im, Gi-Sun,Hwang, Seong-Soo,Baek, Kwang-Soo,Jeon, Byeong-Soon,Park, Sung-Jai,Kim, Hyeon-Shup,Lim, Jeong-Mook The Korean Society of Animal Reproduction 2009 Reproductive & developmental biology Vol.33 No.4

The objective of this study was to determine effects of different culture media. Preantral follicles were mechanically extracted from bovine ovaries and cultured for 16 days in tissue culture medium (TCM)-199, DMEM or alpha-minimal essential medium ($\alpha$-MEM) + 10% FBS + 0.1 mg/ml sodium pyruvate + 100 mIU/ml FSH. The collected primary follicles from ovary were higher than the primary and secondary follicles. The survival rates of the follicles in TCM-199 were significantly higher (p<0.05) than those in DMEM and $\alpha$-MEM. The diameter of the follicles progressively increased during 12 days of culture. The maximum size ($139.1{\pm}5.4\;{\mu}m$) reached on Day 12 of the in vitro culture and decreased on Day 16. These results suggest that in a culture of bovine preantral follicles, TCM-199 is an optimal medium and a longer-term culture of preantral follicles (>12 days) may be needed to form antra.

진동 오차 보상 기법을 적용한 동적 환경에서도 강인한 땅속작물 수확기용 무게 측정 알고리즘 설계

임훈(Hoon Lim),서명국(Myoung-Kook Seo),주영훈(Young Hoon Joo),윤병운(Byong-Un Yun),방병주(Byoung-Ju Bang) 대한전기학회 2020 전기학회논문지 P Vol.69 No.1

In this paper, we propose a system for weighing and verifying the weight of the crop in a stable and robustly in the dynamic environment where vibrations are generated during the harvesting of the field. At present, the method of measuring the weight of the harvest using a mechanical crop harvester is very inefficient. So in order to design the controller to improve the current problem, we derived the formula to reduce the vibration during weight measurement, applied the appropriate algorithm, and verified the performance of the controller through various experiments. Through this study, we are going to develop intelligent underground crop harvesting machines, simplify the process of weight measurement work, and increase the overall efficiency and convenience of field farming.

산불피해지 참나무 맹아림 시업체계에 관한 연구

임주훈 ( Joo Hoon Lim ),지동훈 ( Dong Hun Ji ),이영근 ( Young Geun Lee ),이명보 ( Myung Bo Lee ) 한국산림과학회 2009 한국산림과학회지 Vol.98 No.6

Survival and Meiotic Competence of Mouse Oocytes Originating from Preantal Ovarian Follicles

Hyun Joo Lim,Dong-Hoon Kim,Seongsoo Hwang,Yeoung-Gyo Ko,Jeong-Mook Lim,Boh-Suk Yang,Hwan-Hoo Seong 한국동물번식학회 2007 Reproductive & Developmental Biology(Supplement) Vol.31 No.2s