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Ecology of the Forest Birds in Mt. Chiri, Korea (한국산(韓國產) 산림조류(山林鳥類)의 서식생태(棲息生態) - 지리산지역(智異山地域)을 중심(中心)으로 -)

  • Choi, Jai Sik;Kim, Jai Saing
    • Journal of Korean Society of Forest Science
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    • v.80 no.2
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    • pp.162-176
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    • 1991
  • For the purpose of contributing to wild birds protection and propagation, distribution characteristics and ecological breeding habitats were surveyed in Mt. Chiri from September, 1986 to December, 1989 by the use of the nestboxes installed in four study sites by the altitude. The results were as follows ; 1. During the study period, observed birds were 2,403 individuals belong to 59 species, especially, at the 1,400m above altitude the rare species, Falco tinnunculus and the protecting bird species such as Ninox scutulata, Strix aluco and Prunella collaris were observed. 2. In the inhabitation structure of birds by the altitude, Fringilla montfringilla was the highest dominance (41.33%) among the inhabitated birds in the surveyed area. 3. Phasianus colchicus and Streptopelia orientalis which were mainly inhabited in hilly area were observed until the altitude of 900m. 4. The 92.5% of nest boxes was mainly used by the small birds, Parus spp. and Sitta europaea. These species preferred the nest boxes installed at the edge or along the mountaineering path, because they could get food and water easily from those places. 5. The utilization rate of the nest boxes was showed 86% at 500m, 96% at 900m, 98% at 1,400m and 90% at 1,700m above the altitude, respectively. 6. The breeding rate of birds in the nest boxes was showed from 6% to 46% by altitude. Parus varius was the highest breeding species in the surveyed area. These birds inhabited above 500m laid eggs from 15th, April to 22th, May(n=22), but those above 1,700m laid eggs from 28th, April to 27th, May(n=13), that 13 days were delayed at high altitude. 7. Food items of the chicks of the 5 species collected by the collar method were animal matters ; 91.3% of the food was forest insects such as Phalera asiimilis and Pleuroptya batteata except 8.7% of spiders.

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Possible Use of the Animal By-product Mixture as n Dietary Fish meal Relpacer in Growing Common Carp (Cyprinus carpio) (잉어 사료에 있어 축산 가공 부산 혼합물의 어분 대체 가능성)

  • BAI Sungchul;JANG Hye-Kyung;CHO Eun-Sun
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.31 no.3
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    • pp.380-385
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    • 1998
  • This study evaluated the possible utilization and the replacing range of animal by-product mixture (ABPM) as a dietary fish meal replacer in growing common carp (Cyprinus carpio). ABPM is a mixture of leather meal, meat and bone meal, blood meal and squid liver powder at a specific weight based ratio. Five different diets were formulated on isonitrogenous and isocaloric basis of $40\%$ crude protein and 15.3 KJ/g diet in which white fish meal (WFM) protein was substituted with the ABPM Protein as follows: diet 1, $100\%$ WFM ($0\%$ ABPM, control); diet 2, $75\%$ WFM+$25\%$ ABPM ($25\%$ ABPM); diet $3,\;50\%$ WFM+$50\%$ ABPM ($50\%$ ABPM); diet 4 $25\%$ WFM+$75\%$ ABPM ($75\%$ ABPM); diet $5.0\%$ WFM+$100\%$ ABPM ($100\%$ ABPM). As the dietary protein sources, each diet contained $34.7\%$ of animal protein supplied by white fish meal and/or ABPM and $65.3\%$ of plant protein. After one week of conditioning period, fish averaging 10 g were randomly assigned to each diet treatment as triplicate groups and fed one of the experimental diets for 12 weeks. Weight gain of fish fed diet 1 (control) and 3 were significantly higher than those of fish fed diet 2, 4 and 5 during the first 4 weeks (P< 0.05), while there were no significant differences among all diet groups during the third 4 weeks (P>0.05). Feed conversion ratio of fish fed diet 1 was significantly higher than those fed diet 2, 3, 4 and 5 during the second 4 weeks (P<0.05), while there were no significant differences among all diet groups during the first and the third 4 weeks (P<0.05). There were no significant differences in proximate analysis among fish fed the experimental diets either for the second 4 weeks or the third 4 weeks (P>0.05). These results indicated that ABPM could be used as a fish meal replacer up to $100\%$ in growing common carp.

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Application of ECVAM as a Indicator for Monitoring National Environment in Korea (국토환경 모니터링 지표로서의 국토환경성평가지도 활용방안)

  • Kim, Eunyoung;Jeon, Seong-Woo;Song, Wonkyong;Kwak, Jaeryun;Lee, June
    • Journal of Environmental Policy
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    • v.11 no.2
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    • pp.3-16
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    • 2012
  • Objectives of the Korean Environmental Conservation Value Assessment Map (ECVAM) is to evaluate environmental value used in comprehensive environmental information in order to encourage eco-friendly land use and management. The first research was conducted in 2001 to establish the evaluation items and the criteria of the ECVAM, and the first nationwide map was established in the period of 2003 to 2005. The maps are updated annually to reflect environmental changes of land. The evaluation items and the criteria have been modified based on feasibility studies to improve the accuracy of the maps. This study re-evaluated the ECVAMs from 2005 to 2010 with criteria used in current environment and analyzed the changes in the area of the maps in 6 years. This is also an investigation on the maps whether they are appropriate as an index for sustainable environmental monitoring. The result shows that the 1st grade level of the ECVAM area with the highest conservation value had been expanding since 2005. These changes were analyzed in terms of updating the 4th Forest Map (2008) produced once every 10 years, reflecting the new legal protected areas such as Baekdudaegan Protected Area(2010), and the environmental/ecological assessment items such as the National Ecological Network (2009). This mean the ECVAM are a monitoring index that integrates individual environmental indexes including the increase of forest age and diameter due to sustainable management of forest areas, and the change of conservation areas. Therefore, ECVAM can be used as a new index integrating national environmental indicators for monitoring changes of national environment and policy. In order to utilize the ECVAM, improving accuracy and reducing renewal cycle time of thematic maps are required.

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Effect of Di(2-ethyl hexyl)phthalate(DEHP) on the Onset of Puberty in Female Rat (암컷 흰쥐의 사춘기 개시에 미치는 di(2-ethyl hexyl)phthalate(DEHP)의 효과)

  • Lee, Kyeung-Yeup;Lee, Sung-Ho
    • Development and Reproduction
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    • v.10 no.2
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    • pp.147-154
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    • 2006
  • Phthalates such as di(2-ethyl hexyl)phthalate(DEHP) are industrial chemicals with wide-ranging human exposures because of their use in plastics and other common consumer products. Consequently, their adverse effects as endocrine disruptor in the reproductive physiology of both laboratory rodents and human have been studied extensively. The present study was undertaken to examine whether prepubertal exposure to DEHP affects on the onset of puberty and the associated reproductive parameters such as hormone receptor expressions in female rats. DEHP(100mg/kg/day) was administered daily from postnatal day 25(PND 25) through the day when the first vaginal opening(VO) was observed, and the animals were sacrificed on the next day. Gross anatomy and weight of reproductive tissues were compared to test the DEHP's effects on the cell proliferation. Furthermore, histological studies were performed to assess the structural alterations in the tissues. Specific radioimmunoassay was carried out to measure serum LH levels. To determine the transcriptional changes in progesterone receptor(PR), total RNAs were extracted and applied to the semi-quantitative reverse transcription polymerase chain reaction(RT-PCR). As a result, delayed VO was shown in the DEHP group(PND $37.3{\pm}0.7$) compared to the control group(PND $35.3{\pm}0.7$; p<0.05). DEHP treatment significantly decreased the wet weight of ovaries and uteri compared to the control group(p<0.05). Interestingly, elevation of serum LH levels was shown in the DEHP group(p<0.05). Graafian follicles and corpora lutea were observed only in the ovaries from the control animals. Numerous primary, secondary follicles and small atretic follicles were observed in the ovaries from DEHP-treated animals. Similarly, hypotrophy of luminal and glandular uterine epithelium was found in the DEHP-treated group. These effects were probably due to the inhibitory effects of DEHP on the synthesis and secretion of estrogen from granulosa cells. In the semiquantitative RT-PCR studies, the transcriptional activities of PR in both ovary(p<0.05) and uterus(p<0.01) from DEHP-treated animals were significantly lower than those from the control animals. The present studies demonstrated that the acute exposure to DEHP during the critical period of prepubertal stage could inactivate the reproductive system resulting delayed puberty in female rats.

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Total Parenteral Nutrition-associated Cholestasis in Premature Infants (미숙아에서의 전비경구적 영양 관련 담즙울체)

  • Park, Kyung Pil;Kim, Se Young;Kim, Heng Mi
    • Clinical and Experimental Pediatrics
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    • v.46 no.1
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    • pp.17-23
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    • 2003
  • Purpose : Cholestasis is a major complication in prolonged use of TPN, especially in the neonatal period, but there are few long-term reviews examining the clinical course in premature infants. Thus, in this study, we reviewed premature infants with TPN-associated cholestasis(TPNAC) to determine the incidence, clinical courses and possible risk factors. Methods : Retrospective review of 66 premature infants less than 2,000 gm of birth weight and on TPN for more than two weeks was performed. Cholestasis was defined as a serum direct bilirubin level greater than 2.0 mg/dL. The clinical course of cholestasis was described, and perinatal risk factors were evaluated. Results : TPNAC developed in 21 out of 66 infants(31.8%). The onset was $41.7{\pm}17.4days$ after receiving TPN, and the mean duration was $33.6{\pm}23.4days$. The incidence of TPNAC was significantly correlated with birth weight, and gestational age, and duration of TPN. But, possible etiologic factors, such as incidence of perinatal asphyxia or infection, showed no remarkable differences between infants with TPNAC and those without TPNAC(control). The enteral intake in the third postnatal week was significantly smaller in infants with TPNAC than in the control infants(P=0.033). Conclusion : The enteral intake in the third postnatal week was smaller in the infants with TPNAC than in the control infants. Thus, the incidence of TPNAC may be reduced by increasing the amount of oral intake during TPN in high risk infants.

Long-term Climate Change Research Facility for Trees: CO2-Enriched Open Top Chamber System (수목의 장기 기후변화 연구시설: CO2 폭로용 상부 개방형 온실)

  • Lee, Jae-Cheon;Kim, Du-Hyun;Kim, Gil-Nam;Kim, Pan-Gi;Han, Sim-Hee
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.14 no.1
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    • pp.19-27
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    • 2012
  • The open-top chamber (OTC) system is designed for long term studies on the climate change impact on the major tree species and their community in Korea. In Korea Forest Research Institute (KFRI), the modified OTC system has been operating since September 2009. The OTC facility consists of six decagon chambers (10 meters in diameter by 7 meters high) with controlled gas concentration. In each chamber, a series of vertical vent pipes are installed to disperse carbon dioxide or normal air into the center of the chamber. The OTC is equipped with remote controlled computer system in order to maintain a stable and elevated concentration of carbon dioxide in the chamber throughout the experimental period. The experiment consisted of 4 treatments: two elevated $CO_2$ levels ($1.4{\times}$ and $1.8{\times}$ ambient $CO_2$) and two controls (inside and outdoors of the OTC). Average operational rate was the lowest (94.2%) in June 2010 but increased to 98% in July 2010 and was 100% during January to December 2011. In 2010~2011, $CO_2$ concentrations inside the OTCs reached the target programmed values, and have been maintained stable in 2011. In 2011, $CO_2$ concentrations of 106%, 100% and 94% of target values has been recorded in control OTC, $1.4{\times}$ $CO_2$-enriched OTC and $1.8{\times}$ $CO_2$-enriched OTC, respectively. With all OTC chambers, the difference between outside and inside temperatures was the highest ($1.2{\sim}2.0^{\circ}C$) at 10 am to 2 pm. Temperature difference between six OTC chambers was not detected. The relative humidity inside and outside the chambers was the same, with minor variations (0~1%). The system required the highest amount of $CO_2$ for operation in June, and consumed 11.33 and 17.04 ton in June 2010 and 2011, respectively.

Optimization of the cryopreserved condition for utilization of GPCR frozen cells (GPCR 냉동보관 세포의 활용을 위한 냉동조건의 최적화 연구)

  • Noh, Hyojin;Lee, Sunghou
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.16 no.2
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    • pp.1200-1206
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    • 2015
  • The major target for drug discovery, G-protein coupled receptor (GPCR) is involved in many physiological activities and related to various diseases and disorders. Among experimental techniques relating to the GPCR drug discovery process, various cell-based screening methods are influenced by cell conditions used in the overall process. Recently, the utilization of frozen cells is suggested in terms of reducing data variation and cost-effectiveness. The aim of this study is to evaluate various conditions in cell freezing such as temperature conditions and storage terms. The stable cell lines for calcium sensing receptor and urotensin receptor were established followed by storing cultured cells at $-80^{\circ}C$ up to 4 weeks. To compare with cell stored at liquid nitrogen, agonist and antagonist responses were recorded based on the luminescence detection by the calcium induced photoprotein activation. Cell signals were reduced as the storage period was increased without the changes in $EC_{50}$ and $IC_{50}$ values $EC_{50}:3.46{\pm}1.36mM$, $IC_{50}:0.49{\pm}0.15{\mu}M$). In case of cells stored in liquid nitrogen, cell responses were decreased comparing to those in live cells, however changes by storage periods and significant variations of $EC_{50}/IC_{50}$ values were not detected. The decrease of cell signals in various frozen cells may be due to the increase of cell damages. From these results, the best way for a long-term cryopreservation is the use of liquid nitrogen condition, and for the purpose of short-term storage within a month, $-80^{\circ}C$ storage condition can be possible to adopt. As a conclusion, the active implementation of frozen cells may contribute to decrease variations of experimental data during the initial cell-based screening process.

The Making and Use of the Bifid Ornamental Hairpin Stone Mold Excavated at Neungsan-ri, Buyeo (부여 능산리 출토 가랑비녀 용범(鎔范)의 제작과 사용 양상)

  • LEE, Soleon;KIM, Jiyoung;SEO, Hyunju
    • Korean Journal of Heritage: History & Science
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    • v.54 no.2
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    • pp.4-21
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    • 2021
  • A stone mold from the Sabi period of Baekje was excavated at the western tombs in Neungsan-ri, Buyeo where there was a recent excavation survey (2016). It was believed and reported that such stone molds were used for copper needles during the early Iron Age; however, a close re-examination of the form revealed that they were used for bifid ornamental hairpins. Given its casting form, the stone mold of Neungsan-ri is estimated to have been used to make bifid ornamental hairpins in a ∩ shape, narrowing down toward the tip. It is considered an artifact of the Goryeo dynasty. The stone used to make the bifid ornamental hairpin mold of Neungsan-ri was chlorite-schist, the principal minerals of which include chlorite, amphibole, and talc. Similar rocks are in nearby Buyeo (Oesan-myeon), Cheongyang, Gongju, and Yesan. They are mainly found between Jiseon-ri, Oesan-myeon, Buyeo, Sucheol-ri, Yesane-up, and Yesan. Nearly 70 bifid ornamental hairpins from the Goryeo dynasty were excavated at Neungsan-ri, Buyeo and the surrounding areas. Among them, the bronze ones excavated from the tombs of Songguk-ri, Buyeo are estimated to have been made using this mold as they closely resemble the Neungsan-ri mold. Stone was likely the preferred material for molds to make bronze artifacts as it was easy to sink a die. Regarding the bifid ornamental hairpin cast excavated in Neungsan-ri, they obtained stones in nearby areas 20~50km from their location, made bronze artifacts, and distributed them to nearby sites during the Goryeo dynasty. These artifacts suggest that the casting technology of using a stone mold was still employed then.

Future Prospects of Forest Type Change Determined from National Forest Inventory Time-series Data (시계열 국가산림자원조사 자료를 이용한 전국 산림의 임상 변화 특성 분석과 미래 전망)

  • Eun-Sook, Kim;Byung-Heon, Jung;Jae-Soo, Bae;Jong-Hwan, Lim
    • Journal of Korean Society of Forest Science
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    • v.111 no.4
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    • pp.461-472
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    • 2022
  • Natural and anthropogenic factors cause forest types to continuously change. Since the ratio of forest area by forest type is important information for identifying the characteristics of national forest resources, an accurate understanding of the prospect of forest type change is required. The study aim was to use National Forest Inventory (NFI) time-series data to understand the characteristics of forest type change and to estimate future prospects of nationwide forest type change. We used forest type change information from the fifth and seventh NFI datasets, climate, topography, forest stand, and disturbance variables related to forest type change to analyze trends and characteristics of forest type change. The results showed that the forests in Korea are changing in the direction of decreasing coniferous forests and increasing mixed and broadleaf forests. The forest sites that were changing from coniferous to mixed forests or from mixed to broadleaf forests were mainly located in wet topographic environments and climatic conditions. The forest type changes occurred more frequently in sites with high disturbance potential (high temperature, young or sparse forest stands, and non-forest areas). We used a climate change scenario (RCP 8.5) to establish a forest type change model (SVM) to predict future changes. During the 40-year period from 2015 to 2055, the SVM predicted that coniferous forests will decrease from 38.1% to 28.5%, broadleaf forests will increase from 34.2% to 38.8%, and mixed forests will increase from 27.7% to 32.7%. These results can be used as basic data for establishing future forest management strategies.

The Result of Radiotherapy in Esophageal Carcinoma (식도암의 방사선치료 성적)

  • Gil Hack Joon;Kay Chul Seung;Jang Jee Young;Yoon Sei Chul;Shinn Kyung Sub;Bahk Yong Whee
    • Radiation Oncology Journal
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    • v.10 no.2
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    • pp.193-204
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    • 1992
  • During the period between March 1983 and December 1990, 74 patients with esophageal carcinoma (EG) were treated with radiation therapy (RT) at the Department of Therapeutic Radiology, Kangnam St. Mary's Hospital, Catholic University Medical College. Of these, 6 patients were lost to follow-up, and 13 patients were interrupted. So the remaining 55 patients were analyzed, retrospectively. 32 patients were irradiated with curative aim, 12 patients with palliative intent, 10 patients postoperatively, and 1 patient pre- and post-operatively. Among these 55 patients, 28 patients were treated with chemoradiation modality, and 27 patients with RT alone. All patients were followed for a minimum of 20 months or until death. Of 32 patients irradiated by curative aim, 22 patients (69%) showed partial remission (PR), 6 patients (19%) complete remission (CR). Overall mean survival and two-year survival rate were 15.6 months and 22%. With respect to sex, age, pathologic differentiation, tumor location, tumor size, stage, RT aim, RT response, RT dose, use of chemotherapy and functional categories (FC) of dysphagia at initiation of RT and at finishing RT: Tumor size, stage, RT response had great influences on prognosis and FC at finishing RT had a slight influence on prognosis. Especially, the mean survival and 2-year survival rate in patients with postoperative RT were 24.7 months and 63%, which could be compared with 29.1 months and 43% in radically treated patients with CR. And the mean survival duration and 2-year survival rate in patients irradiated with doses more than 60 Gy were 22.4 months and 29%, and 50~60 Gy were 12.2 months and 12%, respectively. However, no significant difference was shown statistically. Among 12 patients treated with palliative intent, 9 patients (75%) had good improvement in dysphagia and the mean duration of palliative response was 10.6 months.

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