• Title/Summary/Keyword: formation age

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AN EXPERIMENTAL STUDY ON THE HISTOPATHOLOGICAL CHANGE OF THE MANDIBULAR JOINT BY MUSCLE ALTERATION IN RAT (백서교근의 변형에 따른 악관절부의 병리조직학적 연구)

  • Park, Young Chel
    • The korean journal of orthodontics
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    • v.14 no.1
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    • pp.53-65
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    • 1984
  • The purpose of this study was to investigate the histopathological change and adaptation process of the mandibular joint of the rat by muscle alteration. For this study, one hundred and twenty eight rats of 25 - and 60 - day old of age were used. Unilateral and bilateral detachment, with anterior positioning of the Masseter muscle, was performed under anesthesia. The animal was sacrified 10, 20, 50, 80 days postoperatively. This alteration in muscle function led to change in neuromuscular activity and demonstrated the adaptive nature of the condyle cartilage to functional demand. The results were as follows : 1. In the right muscle detached group, operated at 25 days of age, marked decrease on the chondroblastic zone was found in the condyle head on the right side of animals examined 10 days postoperatively. Comparing with the control group, no difference was found on the chondroblastic zone in the condylar head of animals examined 20, 50 and 80 days postoperatively. 2. In the bilateral muscle detached group, operated at 25 days of age, the chondroblastic zone was slightly decreased in the anterior parts of condylar head of animals examined 10 days postoperatively. 3. In the unilateral and bilateral muscle detached group, operated at 60 days of age, no significant change was found in the mandibular joint regardless of the post operative experimental periods. 4. Under Toluidine blue staining, slightly decreased metachromasia was found in the condyle head on the right side of unilateral experimental animals, operated at 25 days of age and examined 10 days postoperatively. 5. Under Masson's trichrome staining, increased metachromasia was found in the condyle head on the right side of unilateral experimental animals, operated at 25 days of age and examined 10 days postoperatively. In summary, the condyle of the rat could respond to changes in neuromuscular activity depend on the level of maturation of the tissue, because the endochondral bone formation of the condyle of the rat was almost ended within 3 months.

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LA-MC-ICPMS U-Pb Ages of the Detrital Zircons from the Baengnyeong Group: Implications of the Dominance of the Mesoproterozoic Zircons (신원생대 백령층군 사암의 쇄설성 저어콘 LA-MC-ICPMS U-Pb 연령: 중원생대 집중연령의 의미)

  • Kim, Myoung Jung;Park, Jeong-Woong;Lee, Tae-Ho;Song, Yong-Sun;Park, Kye-Hun
    • Economic and Environmental Geology
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    • v.49 no.6
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    • pp.433-444
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    • 2016
  • The U-Pb ages of detrital zircons from the Baengnyeong Group were determined by LA-MC-ICPMS, yielding condensed age population in the range from 1100 Ma to 1800 Ma corresponding to the Mesoproterozoic to late Paleoproterozoic. However, detrital zircons of ca.1800-2000 Ma or ca. 2500 Ma ages, which appear frequently in the lower Paleozoic Joseon Supergroup and the upper Paleozoic Pyeongan Supergroup are lacking in the Baengnyeong Group. Such characteristics are identical to those of the Neoproterozoic Sangwon System of North Korea, suggesting that the Baengnyeong Group might be the southwestern extension of the Sangwon System. The zircon age distribution patterns from the Impi Formation in the Gunsan area closely resemble those of the Baengnyeong Group, implying possible correlation of the Impi Formation to the Sangwon System. Therefore, the Mesoproterozoic detrital zircons reported from the Hwangangni Formation of the Okcheon Metamorphic Belt and the Myobong, Sambangsan and Sesong Formations of the Taebaeksan Basin might be derived from the provenances within the Korean peninsula.

Geomorphological Processes of Fluvial Terraces at the River Basins in the East Coast in the Southern Taebaek Mountain Range (태백산맥 남부 동해안 하천 유역의 하안단구 지형 형성)

  • Lee, Gwang-Ryul
    • Journal of the Korean Geographical Society
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    • v.49 no.1
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    • pp.1-17
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    • 2014
  • This study estimates geomorphological processes of fluvial terraces by uplifts and bedrock features, by the analyses of topography, distribution, formation age and incision rate of fluvial terraces using Gwang-cheon River in Uljin, Namdae-cheon River in Pyeonghae and Osip-cheon River in Yeongdeok located in the southern Taebaek Mountain Range. The tectonic and climatic terraces I in the upper reaches of Gwang-cheon River with an altitude from riverbed of 9~12m indicate the formation age of MIS 2 with a incision rate of 0.40m/ka. However, the tectonic and climatic terraces I in the upper reaches of Osip-cheon River with an altitude from riverbed of 7~10m show the formation age of MIS 3 with an incision rate of 0.10m/ka. These results suggest that the uplift rate in the Gwang-cheon River basin is likely to be higher than that in the Osip-cheon River basin. Unlike the lower reaches of Osip-cheon River, the thalassostatic terraces are not found in the lower reaches of Gwang-cheon River, because the basin has low maintainable ability of landforms in river valley due to high uplift rate and bedrock properties resistant to weathering and erosion. On the other hand, the lowest tectonic and climatic terraces in the study areas indicate different formative ages and the terraces during the cooling stage in interglacial as well as during interstadial are also found. Therefore, this study suggests that chronological method for fluvial terrace by the previous developmental model of climatic terrace should be reconsidered.

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Occurrence of the lowermost part of the Yucheon Group and its SHRIMP U-Pb ages in Hyeonpoong and Bugok areas (현풍-부곡일원 최하부 유천층군의 산상과 SHRIMP U-Pb 연대)

  • Ghim, Yong Sik;Ko, Kyoungtae;Lee, Byung Choon
    • Economic and Environmental Geology
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    • v.53 no.4
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    • pp.397-411
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    • 2020
  • The Cretaceous Yucheon Group is volcano-sedimentary successions that are formed by volcanic activities of the Gyeongsang Volcanic Arc. Lack of the detailed field researches on the Yucheon Group results in poor understanding of the formation time and the tempo-spatial development of the volcanic arc. Also, this causes difficulties to reconstruct the depositional history from the Sindong and Hayang groups to the Yucheon Group. In this study, we conducted field research targeting to the interface between topmost part of the Hayang Group and the lowermost part of the Yucheon Group from Hyeonpoong to Bugok areas. We also identified depositional timing of the lowermost part of the Yucheon Group using SHRIMP U-Pb zircon age dating. This Yucheon Group is composed of tuff and lapilli tuff, conformably overlying the Jindong Formation. The results of SHRIMP U-Pb zircon age are 97 to 96 Ma, indicating cessation of deposition of the Hayang Group at 97 to 96 Ma by input of pyroclastic materials into the Jinju Subbasin during the explosive volcanic eruptions from the Gyeongsang Volcanic Arc. In comparison with field researches and results of LA-ICP-MS zircon U-Pb age dating (88-85 Ma) of the lowermost part of the Yucheon Group in Gyeongju areas, the volcanic activities that formed Yucheon Group and their influence ranges varied tempo-spatially. This is probably due to distance difference from the volcanic arc or establishment of the paleo-drainage system from the Gyeongsang Volcanic Arc to nearby lowlands.

Geomorphic Evolution of Fluvial Terraces at Yeongdong.Yeongseo Streams in Gangwon Province, Korea (강원도 영동.영서 하천의 하안단구 지형 발달 - 내린천, 연곡천, 골지천, 오십천을 사례로)

  • Yoon, Soon-Ock;Hwang, Sang-Ill;Lee, Gwang-Ryul
    • Journal of the Korean Geographical Society
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    • v.42 no.3 s.120
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    • pp.388-404
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    • 2007
  • This study interprets evolution of fluvial terraces along the four Yeongdong- and Yeongseo streams such as Naerin River, Yeongok River, Golji River and Osip River, in Gangwon Province based on the tectonics. The results from the analyses of the distribution pattern of fluvial terraces and incision rates of rivers show distinctively the evidence as the axis of uplift by Taebaek Mountains, especially on the 4th, 5th and 6th terraces in upper reach of Osip River among the four streams. The axis of uplift extends to the zone of $30\sim40km$ in width as well as the divide. The difference of uplift between upper and middle reaches of Naerin River and total reach of Golji River wasn't found from the height from riverbed by the active uplifting along all reaches, estimated to be set in inner area of uplift zone. Incision rate of period between formation age of 2nd terrace and 1st terrace is calculated $0.13\sim0.22m/ka$, and incision rate of period between formation age of 1st terrace and Present is diversely calculated $0.17\sim0.27m/ka$ by the climatic discrepancy between the two periods. The incision rate of Yeongdong streams whose mouths reach to the sea level eroded actively more than Yeongseo streams in the uplift zone. And Yeongdong streams between formation age of 1th terrace and present appears to much higher than that of Yeongseo streams, due to active down-cutting in oder to balance against the sea level.

The Influence of Media Advertisements on Forming a Positive Image of Vocational Colleges : A Focus on New Students at K Vocational College in the Jeonbuk (매체별 광고가 전문대학에 대한 긍정적 이미지 형성에 미치는 영향 : 전북지역 K전문대학 신입생을 중심으로)

  • Junsu Han
    • The Journal of the Convergence on Culture Technology
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    • v.10 no.5
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    • pp.593-600
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    • 2024
  • This study aimed to investigate the extent to which media advertisements conducted by vocational colleges (such as SNS, banners, university information boards in high schools, terminal advertisements, local daily newspaper advertisements, and elevator video advertisements) influence the formation of a positive image of the college among incoming students. To this end, a total of 430 freshmen at K Vocational College in Jeonbuk were asked about the frequency of their exposure to the college's media advertisements for each type of media. Additionally, they were asked about the impact these advertisements had on forming a positive image of the college, and the results were analyzed accordingly. The frequency of exposure to the advertisements was measured to verify the exposure effect of the advertisements themselves. To determine the impact of the frequency of exposure to each type of media on the formation of a positive image, correlation analysis and regression analysis were conducted. The key findings are as follows: First, while there were differences in the frequently encountered media among different age groups, banners and SNS advertisements were the most frequently encountered when considering all age groups collectively. Second, regarding the impact of the frequency of exposure to each type of media on the formation of a positive image of the college, elevator advertisements had the most significant effect, followed by banner advertisements. The purpose of this study is to aid in the formulation of the college's promotional strategies, with the expectation that the college will achieve better results through more efficient advertising.

A Study on Sedimentology of the Mesozoic Munamdong Formation, Northeastern Gyeonggi Massif, Korea (경기육괴 북동부에 분포하는 중생대 문암동층의 퇴적학적 연구)

  • Choi, Young-Gi;Ryu, In-Chang
    • Economic and Environmental Geology
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    • v.47 no.5
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    • pp.517-532
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    • 2014
  • The Munamdong Formation is a small scale sedimentary deposit which is located in Yuljeonri, Naemyeon, Hongcheon Gangwon-do. In order to understand the depositional environment and its sequential change in the formation, sedimentary facies analysis was conducted. The result indicates that the Munamdong Formation began to be deposited in alluvial fan system accompanying volcanic activity and gradually deposited in lake system. As well, U-Pb, K-Ar and $^{40}Ar/^{39}Ar$ ages are determined from the Munamdong Formation. The SHRIMP U-Pb Phanerozoic Eon age of the detrital zircons in the middle part of the Munamdong formation yields $229.8{\pm}2.5Ma$. The K-Ar and $^{40}Ar/^{39}Ar$ ages of the volcanic rock in the lowermost part of the Munamdong formation are $203.7{\pm}3.9Ma$ and $227.4{\pm}8.4Ma$ respectively. These results confirm that the Munamdong Formation was deposited during the Late Triassic, indicating that the basin might be formed due to post-collisional rifting or collapsing.

A Clinical Review of Lung Abscess - 27 cases - (폐농양의 임상적 고찰)

  • 김민호
    • Journal of Chest Surgery
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    • v.20 no.3
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    • pp.552-556
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    • 1987
  • During the preantibiotic era, lung abscess carried a high mortality, however, with the introduction of penicillin and subsequently other antibiotics, significant improvement was resulted. Clinical review was performed on 27 cases of lung abscess, those were admitted and treated at the Department. of Thoracic and Cardiovascular Surgery, Chonbuk University Hospital, from 1979 to August, 1986. The following results were obtained. The most common age of occurrence was between the age of 40 and 60 [14 cases] and 22 cases were male patients. The common symptoms were cough, putrid sputum production, fever and chilliness. Numerous etiological factors may play a role in the formation of lung abscess; pneumonia [7 cases], aspiration [5 cases], bronchiectasis [2 cases], liver abscess [1 case] and broncholith [1 case]. The bacteriologic study revealed increased incidence of Enterobacteriaceae [15 cases]. The treatment methods were postural drainage [12 cases]. pneumonostomy [5 cases], lobectomy [8 cases], thoracostomy [2 cases].

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Population Synthesis Models for the Sextans and Carina Dwarf Spheroidal Galaxies

  • Joo, Seok-Joo;Lee, Young-Wook
    • Bulletin of the Korean Space Science Society
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    • 2003.10a
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    • pp.78-78
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    • 2003
  • Dwarf galaxies are the most common type of galaxy in the universe and believed to be basic building blocks of the large scale structures. In order to understand the formation history of these galaxies, we selected two well-observed galaxies in the Local Group and constructed the stellar population models including HB stars. We employed Y$^2$ Isochrones (Yi et al. 2001) and HB tracks (Yi et al. 1997) for stellar population synthesis. Our models show that (1) the Carina dSph has several distinct populations with age of ∼10.5, 5.8, 4.1, 2.8 and 1.0 Gyrs, and (2) stellar populations of the Sextans dSph are constructed in terms of the two populations with age of ∼ 11 and ∼2.5 Gyrs. Observational data were kindly provided by Lee et al. (2003, in preparation) and Monelli et al. (2003) for Sextans and Carina dsphs, respectively.

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A Case Study of Food Qualiy in a Hospital Foodservice System -With Special Reference to Patient Satisfaction- (병원영양과의 급식 평가 사례 연구 -환자 만족도를 중심으로-)

  • 김혜진
    • Journal of Nutrition and Health
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    • v.29 no.3
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    • pp.348-356
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    • 1996
  • A survey of one hospital foodservice system in Seoul was undertaken and detailed in formation was collected from 538 patients. Patient satisfaction with the quality of hospital food and food-related service was evaluated by questionnaire survey. It was measured by assessing 24 variables. The effect of medical treatments, age, length of stay and appetite on patients' satisfaction satisfied with the food served, although the variety of food and seasoning of food received the lowest score. The highest rated items were attitude of personnel serving food, the portion size of cooked rice, and the cleanliness of dishes and tray. Younger patients were significantly less satisfied than were older patients. Female patients were significantly more satisfied nificantly more satisfied than were other patients. Medical treatments, age, length of stay of stay and appetite were found to be significantly correlated with patient satisfaction scores. Foodservice attributes for improvement were taste of meals, selection and variety of food and temperature of food.

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