• Title/Summary/Keyword: 연구상

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The Estimation of Gross Primary Productivity over North Korea Using MODIS FPAR and WRF Meteorological Data (MODIS 광합성유효복사흡수율과 WRF 기상자료를 이용한 북한지역의 총일차생산성 추정)

  • Do, Na-Young;Kang, Sin-Kyu;Myeong, Soo-Jeong;Chun, Tae-Hun;Lee, Ji-Hye;Lee, Chong-Bum
    • Korean Journal of Remote Sensing
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    • v.28 no.2
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    • pp.215-226
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    • 2012
  • NASA MODIS GPP provides a useful tool to monitor global terrestrial vegetation productivity. Two major problems of NASA GPP in regional applications are coarse spatial resolution ($1.25^{\circ}{\times}1^{\circ}$) of DAO meteorological data and cloud contamination of MODIS FPAR product. In this study, we improved the NASA GPP by using enhanced input data of high spatial resolution (3 km${\times}$3 km) WRF meteorological data and cloud-corrected FPAR over the North Korea. The improved GPP was utilized to investigate characteristics of GPP interannual variation and spatial patterns from 2000 to 2008. The GPP varied from 645 to 863 $gC\;m^{-2}\;y^{-1}$ in 2000 and 2008, respectively. Mixed forest showed the highest GPP (1,076 $gC\;m^{-2}\;y^{-1}$). Compared to NASA GPP (790 $gC\;m^{-2}\;y^{-1}$);FPAR enhancement increased GPP (861) but utilization of WRF data decreased GPP (710). Enhancements of both FPAR and meteorological input resulted in GPP increase (809) and the improvement was the greatest for mixed forest regions (+10.2%). The improved GPP showed better spatial heterogeneity reflecting local topography due to high resolution WRF data. It is remarkable that the improved and NASA GPPs showed distinctly different interannual variations with each other. Our study indicates improvement of NASA GPP by enhancing input variables is necessary to monitor region-scale terrestrial vegetation productivity.

Reproductive Growth of Seeds and Overwintered Stump of Bulrush (Scirpus juncoides Roxb.) (올챙고랭이(Scirpus juncoides Roxb.) 종실(種實) 및 월동주기부(越冬株基部)의 번식생장(繁殖生長)에 관한 연구(硏究))

  • Huh, S.M.;Guh, J.O.
    • Korean Journal of Weed Science
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    • v.7 no.1
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    • pp.35-44
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    • 1987
  • Differing in water conditions, the dry matter weight per plant was highest at 0 cm flooding depth, and was decreased at above 2 cm flooding depths. The shoot and spikes per pot developed best at flooding depths of 0 and 2 cm, but worst at -5cm or above 4cm flooding depths. The dry matter weight of shoots was linearly increased, but the weight of roots was sharply decreased according to high temperature after flower initation. The shoots and spikes per pot developed more effectively at 25$^{\circ}C$ than at 35 or 15$^{\circ}C$. The number of shoot and spike per pot were decreased according to higher shading. The effects of shading of 25-45% were not significantly small. The natural white and yellow spectra were the most effective to increase dry matter weight, shoots and spikes per pot. The dry matter weights of shoot and root per plant were not significantly different among at: 50 and 75% clay. The number of shoots were best and continuously increased at 75% clay, and the increments at 0 and 100% clays showed the lag period at early stage. The pattern of spikes was similar to shoots with less difference in various clay composition. The dry matter weight per plant in paddy field and upland field was basically similar. The numbers of shoot and spike were increased in response to increased fertilizer levels up to 20Kg per 10a of each component.

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A Reinvestigation on Key Issues Associated with the Yimjin(1712) Boundary Making and Demarcation: Location of 'Yipjiamlyu' and the Confluence of 'Tomungangweon' into the Sungari River (임진정계시 '입지암류(入地暗流)'의 위치와 '토문강원(土門江源)'의 송화강 유입 여부)

  • Lee, Kang-Won
    • Journal of the Korean Geographical Society
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    • v.50 no.6
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    • pp.571-605
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    • 2015
  • This research revealed that 'Yipjiamlyu' in the Mukedeng's map is geographically 'a beginning point of underf low,' whose location is on the Heishigou's riverbed(E.L. 1,840m) in the NNE side of Daegakbong peak, and that 'Tomungangweon'(Heishigou) is one of the upstream reach of the Sungari River, which, according to historical documents and my fieldwork, Mukedeng also knew at the time of Yimjin(1712) Boundary Making and Demarcation(YBMD). These findings suggest the need to reinterpret the processes of YBMD. Mukedeng set up the Baekdusanjeonggyeobi on the mistaken assumptions on the linkage of 'Yipjiamlyu' and Tumen River. It should have been set up on the Daeyeonjibong peak. Mukedeng found the 'Yipjiamlyu' on the riverbed of 'Tomungangweon'(Heishigou), went downstream, and realized that this river did not flow into the Tumen River. During the search for the source of Tumen River, he found a water stream, and regarded it as the source of Tumen River. He speculated that the water at the 'Yipjiamlyu' flows through the underground to reappear at the his 'identified' source of Tumen River. Consequently, he adjured the construction of demarcation from Baekdusanjeonggyeobi through 'Yipjiamlyu' to the his 'identified' source of Tumen River. The water stream pointed as the source of Tumen River, however, was not part of the upstream reach of Tumen River. Actually, Korean officials, who were in charge of establishing boundary features, set up the demarcation from Baekdusanjeonggyeobi through Huanghuasongdianzi to the true source of Tumen River identified by themselves, which Mukedeng had not intended. The ambiguity of the location of 'Yipjiamlyu' caused a difference between Mukedeng's original request and Korean officials' implementation in the boundary demarcation. Throughout the whole processes of YBMD, Korea(Joseon) and China(Qing) both mistook the real geography of the river system. Their understanding on Yalu River system was correct. But the identification of the spring source of the Tumen River by Korean participants was the only geographically correct result related on this river system in YBMD.

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Glomus Tumor in Soft Tissue (연부 조직에 발생한 사구종)

  • Kim, Do-Yeon;Lee, Soo-Hyun;Kim, Min-Ju;Shin, Kyoo-Ho
    • The Journal of the Korean bone and joint tumor society
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    • v.15 no.1
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    • pp.34-43
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    • 2009
  • Purpose: Glomus tumors are rare benign vascular tumors, usually located in the skin or soft tissue of extremities. Approximately 30-50% of glomus tumors occur in subungal area, but glomus tumors have been described in every location even where glomus bodies are not or rarely present. The purpose of this study was to identify clinical, histologic and MRI characteristics of soft tissue glomus tumor. Materials and Methods: Between 1993 and 2008, eight patients underwent surgery of soft tissue Glomus tumor at our institution. Exclusion criteria were patients with Glomus tumors in digits, stomach, trachea and glomus tympanicum. We analyzed medical records, interviews, physical examinations, MR findings and histolocial types retrospectively. Results: There were four men and four women. The mean age was fourty-seven years. The mean prevalence time was eight-point-nine years. In the classic triad of symptoms, all eight patients had pain and tenderness. Two patients complained of cold sensitivity. Two showed skin color changes. After surgery, two showed symptom improvement (VAS $9^{\circ}{\rightarrow}8$, $8^{\circ}{\rightarrow}5$) and?six showed complete disappearance of symptoms. Slightly symptom improvemented (VAS $9^{\circ}{\rightarrow}8$) one had additional surgery two times after first surgery due to relapse/remaining Glomus tumor. The mean size was 13.9 mm. In histology, six were 'solid glomus tumor', one was a mixture of 'solid glomus tumor' and 'lomangioma' and one was 'malignant glomus tumor'. MR findings showed isointense signal on T1 image, high signal on T2 image and strong enhancement on the Gadolinium enhanced image. Conclusion: Glomus tumor has low recurrence rate and malignant change, rapid diagnosis and surgical excision is critical in treatment to prevent unnecessary pain of patient.

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Analysis on Distribution Characteristics of Mammals in Relation to Altitude in Juwangsan National Park (주왕산국립공원에 서식하는 포유동물의 고도에 따른 분포 특징의 분석)

  • Chung, Chul-Un
    • Journal of Ecology and Environment
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    • v.29 no.6
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    • pp.511-520
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    • 2006
  • The study analyzed the distribution of mammalia per altitude in Gamebong, the highest trail of Juwangsan National Park and confirmed the inhabitation of 22 different species inhabiting in the park. Starting from 200 m to 800 m above the sea level was segmented into 100 m unit. The result of analysis has shown that the Tamias sibiricus is the dominant specie throughout in all segments. Species confirmed to be inhabiting in all segments of research areas were Mustela sibirica, Caproelus pygargus and squirrel. By analyzing the confirmed Field Sign basing from the observation point, it has shown close relations between types of species and population following the increase in altitude (y=-0.0234 + 25.552, $R^2$=0.9296, $F_{0.05}$(1,4)=7.71, p<0.05). However, the result of analysis targeting nine species inhabiting in at least five out of six 100 m segmented units has shown that only two species, Apodemus sgrarius (y=-0.034X+25.2, $R^2$=0.905, $F_{0.05}$(1, 4)=38.169, p<.0.01) and Sciurus vulgaris (y=-0.0154X+ 12.819, $R^2$=0.781, $F_{0.05}$(1, 4)=14.270, p<0.05) were affected by the altitude. Therefore, it is judged that the distribution of species does not follow the altitude variation but follows the food conditions and the structure of habitat. The result of analysis of Box and Whisker Diagram had shown lowest quartile deviation($Q_U-Q_L$) in Nature Restoration Area that is located in $200{\sim}300m$ above the sea level, where hikers are prohibited from entering. In $500{\sim}600m$ above the sea level segment that has similar food environment and trail, it has shown the widest distribution. Further research is required on this segment for the excretion drops of Prionailurus bengalensis, a Grade II class of endangered species, were found on the trails.

Characteristics of Diurnal Variation of High PM2.5 Concentration by Spatio-Temporal Wind System in Busan, Korea (시·공간적 풍계에 따른 부산지역 고농도 PM2.5의 일변화 특성)

  • Kim, Bu-Kyung;Lee, Dong-In;Kim, Jeong-Chang;Lee, Jun-Ho
    • Journal of the Korean earth science society
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    • v.33 no.6
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    • pp.469-480
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    • 2012
  • This study was to analyze the characteristics of diurnal variation of high $PM_{2.5}$ concentration, $PM_{2.5}/PM_{10}$ concentration ratio by spatio-temporal wind system (wind speed and wind direction) for high $PM_{2.5}$ concentration (over the 24 hr environmental standard of $PM_{2.5}$, $50{\mu}g/m^3$) in the air quality observation sites (Jangrimdong: Industrial area, Jwadong: Residential area) that were measured for 3 years (2005. 12. 1-2008. 11. 30) in Busan. The observation days of high $PM_{2.5}$ concentration were 182 at Jangrimdong and 27 at Jwadong. The seasonal diurnal variation of hourly mean of high $PM_{2.5}$ concentration and of $PM_{2.5}/PM_{10}$ concentration ratio showed a similar pattern that had higher variation at dawn, and night and in the morning than in the afternoon. Durning daytime in summer at Jwadong, the $PM_{2.5}/PM_{10}$ concentration ratio increased because a secondary particulate matter, which was created by photochemical reaction, decreased the coarse particles of $PM_{10}$ more than the fine particles of $PM_{2.5}$ concentrations in ocean condition. We did an analysis of spatio-temporal wind system (wind speed range and wind direction) in each time zone. The result showed that high $PM_{2.5}$ concentration at Jangrimdong occurred due to the congestion of pollutants emissions from the industrial complex in Jangrimdong area and the transportation of pollutants from places nearby Jangrimdong. It also showed that high $PM_{2.5}$ concentration occurred at Jwadong because of a number of local residential and commercial activities that caused the congestion of pollutants.

Onion Beverages Improve Amyloid β Peptide-Induced Cognitive Defects via Up-Regulation of Cholinergic Activity and Neuroprotection (양파(Allium cepa L.) 음료의 콜린성 활성 증가 및 뇌신경세포 보호로 인한 Amyloid β Peptide 유도에 대한 인지장애 개선 효과)

  • Park, Seon Kyeong;Kim, Jong Min;Kang, Jin Yong;Ha, Jeong Su;Lee, Du Sang;Kim, Ah-Na;Choi, Sung-Gil;Lee, Uk;Heo, Ho Jin
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.45 no.11
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    • pp.1552-1563
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    • 2016
  • To examine the cognitive function of onion (Allium cepa L.) beverages (odourless and fortified), we analyzed in vitro neuronal cell protection against $H_2O_2$-induced cytotoxicity and performed in vivo tests on amyloid beta ($A{\beta}$)-induced cognitive dysfunction. Cellular oxidative stress and cell viability were evaluated by DCF-DA assay and MTT assay. These results show that fortified beverage resulted in better neuronal cell protection than odourless beverage at lower concentration ($0{\sim}100{\mu}g/mL$). Fortified beverage also showed more excellent acetylcholinesterase (AChE) inhibitory activity ($IC_{50}$: 4.20 mg/mL) than odourless beverage. The cognitive functions of odourless beverage and fortified beverage in $A{\beta}$-induced neurotoxicity were assessed by Y-maze, passive avoidance, and Morris water maze tests. The results show improved cognitive function in both groups treated with beverages. After in vivo tests, cholinergic activities were determined based on AChE inhibition and acetylcholine levels, and antioxidant activities were measured as SOD, oxidized glutathione (GSH)/total GSH ratio, and MDA levels in mouse brain tissue. In a Q-TOF UPLC/MS system, main compounds were analyzed as follows: odourless beverage (five types of sugars and three types of phenolics) and fortified beverages (six types of phenolics and two types of steroidal saponins).

Colon Interposition as a Gastric Substitute after Performing Gastrectomy in Patients with Gastric Cancer (위암 환자에서 위 절제술 후 결장 간치술)

  • Lee, Jun-Hyun;Hur, Hoon;Jeon, Hae-Myung;Kim, Wook
    • Journal of Gastric Cancer
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    • v.8 no.4
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    • pp.217-224
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    • 2008
  • Purpose: For most surgeons, colon interposition after gastrectomy remains an infrequently performed procedure because of its complexity. The aim of this study was to assess its technical feasibility and safety as a post-gastrectomy reconstruction method by reviewing our experience with colon interposition. Materials and Methods: From March 2001 to February 2002, 30 colon interpositions after-gastrectomy were done with using the ileo-ascending or transverse colon. We analyzed the clinicopathologic features and the surgical outcomes. Results: There were 16 males and 14 females in this study with a mean age of 67.5 years (range: 31 to 76 years). Twenty-five ascending colons and 5 transverse colons were used for the interposition, respectively. The mean operation time was 373 minutes (range: 204 to 600 minutes). There were 9 operative morbidities (30%) and 1 operative mortality. The restoration of bowel motility was noted at 3.8 postoperative days; a soft diet was started at 4.9 postoperative days and the duration of the hospital stay was 18.2 days. The percentage of weight loss in the patients with total, proximal and distal gastrectomy was 16.3%, 14.0% and 8.8%, respectively, at 6 months, and thereafter the weight loss gradually recovered as 8.1%, 7.5% and 5.6%, respectively, at 5 years postoperatively. Gastric stasis was the one of the most meaningful long-term complications, and especially in the patients who underwent distal gastrectomy with colon interposition. Conclusion: Colon interposition after gastrectomy was a very complex procedure with a long operating time and many anastomosis sites. The postoperative outcomes failed to achieve satisfactory weight gain and the patients displayed postprandial symptoms. This suggested that this procedure was not an appropriate procedure for conventional reconstruction after gastrectomy.

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Molecular Cytogenetic Characterization of Supernumerary Marker Chromosomes by Chromosomal Microarray (염색체 마이크로어레이를 이용한 표지염색체의 분자세포유전학적 특성)

  • Bae, Mi-Hyun;Yoo, Han-Wook;Lee, Jin-Ok;Hong, Maria;Seo, Eul-Ju
    • Journal of Genetic Medicine
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    • v.8 no.2
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    • pp.119-124
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    • 2011
  • Purpose: Supernumerary marker chromosome (SMC) could be associated with various phenotypic abnormalities based on the chromosomal origin of SMCs. The present study aimed to determine the genomic contents of SMCs using chromosomal microarray and to analyze molecular cytogenetic characterizations and clinical phenotypes in patients with SMCs. Materials and Methods: Among patients with SMCs detected in routine chromosomal analysis, SMCs originating from chromosome 15 were excluded from the present study. CGH-based oligonucleotide chromosomal microarray was performed in 4 patients. Results: The chromosomal origins of SMCs were identified in 3 patients. Case 1 had a SMC of 16.1 Mb in 1q21.1-q23.3. Case 2 showed 21 Mb gain in 19p13.11-q13.12. Case 3 had a 4.5 Mb-sized SMC rearranged from 2 regions of 2.5 Mb in 22q11.1-q11.21 and 2.0 Mb in 22q11.22-q11.23. Conclusion: Case 1 presented a wide range of phenotypic abnormalities including the phenotype of 1q21.1 duplication syndrome. In case 2, Asperger-like symptoms are apparently related to 19p12-q13.11, hearing problems and strabismus to 19p13.11 and other features to 19q13.12. Compared with cat-eye syndrome type I and 22q11.2 microduplication syndrome, anal atresia in case 3 is likely related to 22q11.1-q11.21 while other features are related to 22q11.22-q11.23. Analyzing SMCs using high-resolution chromosomal microarray can help identify specific gene contents and to offer proper genetic counseling by determining genotype-phenotype correlations.

Osteoporotic Vertebral Fractures: SPECT Findings (골다공증에 동반된 척추골절의 골 SPECT 소견)

  • Baik, Jun-Hyun;Park, Young-Ha;Ihn, Yon-Kwon;Kim, Sung-Hoon;Chung, Yong-An;Yoo, Ie-Ryung;Kim, Jee-Yeung;Jung, Hyun-Seok;Sohn, Hyung-Seon;Chung, Soo-Kyo
    • The Korean Journal of Nuclear Medicine
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    • v.38 no.6
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    • pp.522-527
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    • 2004
  • Purpose: The purpose of this study was to evaluate the usefulness of single photon emission computed tomography (SPECT) of bone using Tc-99m MDP in the diagnosis of osteoporotic vertebral fractures. Materials and Methods: Thirty two patients with osteoporotic vertebral fracture were included in this study (mean age: $67{\pm}8$, male: 5, female: 27). Seventy nine vertebral fractures were detected (38 thoracic/thoracolumbar lesions and 41 lumbar lesions), which were classified by type of deformity (wedge, biconcave or compression). The patterns and locations of increased uptakes were examined and analyzed. Results: Forty seven wedge fractures, 20 biconcave fractures and 12 compression fractures were found. Diffuse and asymmetric uptakes were common in fractured bodies. More than one uptake were examined in 69 posterior elements of fractured vertebrae (87.3%) including 40 of 47 wedge fractures (85.1%), 17 of 20 biconcave fractures (85.0%) and 12 of 12 compression fractures (100%). Wedge fractures were predominant fracture in thoracic/thoracolumbar spine whereas incidence of biconcave or compression type war similar to that of wedge fracture in lumbar spine (p=0.04). Spinous process uptake was more frequently seen in lumbar lesions than thoracic/thoracolumbar lesions (p=0.009). Facet joint uptake in biconcave fracture was more common in lumbar spine (92.3%) than thoracic/thoracolumbar spine (57.1%). Spinous process uptake in biconcave fracture was also more frequently detected in lumbar spine (p=0.043). Conclusion: Bone SPECT was useful in the evaluation of osteoporotic vertebral fracture, especially posterior elements of vertebrae.