• Journal of Korean Neurosurgical Society
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• 제30권2호
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• pp.150-155
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• 2001

Between January 1995 and May 1998, 177 patients with proven lumbar disc herniation were treated by microdiscectomy or by percutaneous endoscopic discectomy(PED). Among them, 43(24.2%) patients underwent PED and were followed for long term outcome. We included only those patients who were followed up more than 13 months. Three patients who did not improved immediately after PED and underwent microdiscectomy were excluded for this study. Of remaining 40 patients, there were 22 men and 18 women who ranged in age from 23 to 68 years (mean 38.1 years). The disc herniations were located at L1-2(1), L2-3(1), L3-4(1), L4-5(26) and L5-S1(11). Three patients were treated by biportal approach. The mean follow up period was 34.7 months(range 13-47 months). Overall, excellent and good results were achieved in 12(30%) and 19(47.5%) patients, and fair and poor results in 7(17.5%) and 2(5%) patients, respectively. Thirty-eight(95%) patients returned to their previous works and the mean duration was 5.7 months. Thirty-three(82.5%) patients answered that they would recommend this procedure to others. There was no complication except for one patient who suffered from discitis. The indication of PED is restricted to contained or small subligamentous lumbar disc herniation without stenosis, spondylolisthesis and sequestration. PED can be performed under local anesthesia and tissue trauma, risk of epidural scarring, hospitalization time and postoperative morbidity are minimal. The result of the present study justify the assumption that PED can be a surgical alternative for patients suitable for its indications.

• Molecules and Cells
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• 제42권10호
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• pp.693-701
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• 2019

Plants monitor changes in day length to coordinate their flowering time with appropriate seasons. In Arabidopsis, the diel and seasonal regulation of CONSTANS (CO) protein stability is crucial for the induction of FLOWERING LOCUS T (FT) gene in long days. FLAVIN-BINDING, KELCH REPEAT, F-BOX 1 (FKF1) and ZEITLUPE (ZTL) proteins control the shape of CO expression profile antagonistically, although regulation mechanisms remain unknown. In this study, we show that GIGANTEA (GI) protein modulates the stability and nuclear function of FKF1, which is closely related to the stabilization of CO in the afternoon of long days. The abundance of FKF1 protein is decreased by the gi mutation, but increased by GI overexpression throughout the day. Unlike the previous report, the translocation of FKF1 to the nucleus was not prevented by ZTL overexpression. In addition, the FKF1-ZTL complex formation is higher in the nucleus than in the cytosol. GI interacts with ZTL in the nucleus, implicating the attenuation of ZTL activity by the GI binding and, in turn, the sequestration of FKF1 from ZTL in the nucleus. We also found that the CO-ZTL complex presents in the nucleus, and CO protein abundance is largely reduced in the afternoon by ZTL overexpression, indicating that ZTL promotes CO degradation by capturing FKF1 in the nucleus under these conditions. Collectively, our findings suggest that GI plays a pivotal role in CO stability for the precise control of flowering by coordinating balanced functional properties of FKF1 and ZTL.

• 한국지하수토양환경학회지:지하수토양환경
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• 제17권4호
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• pp.1-8
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• 2012

The success of stabilization treatment in heavy metal contaminated sediment depends on the heavy metal bioavailability reduction through the sequestration of the heavy metals. This study was performed to assess the changes in the bioavailability of Pb or Cd in the Pb or Cd contaminated sediments by using birnessite and hydroxyapatite as stabilizing agents. The toxicity tests were carried out using a microorganism (Vibrio fischeri), an amphipod (Hyalella azteca) and an earthworm (Eisenia foetida). With Vibrio fischeri, the toxicities of both Pb and Cd were reduced by more than ten times in the presence of birnessite and hydroxyapatite compared to that of in the absence of birnessite and hydroxyapatite. The concentrations of Pb and Cd in the contaminated sediments were lethal to Hyalella azteca, however, in the presence of birnessite and hydroxyapatite more than 90%, on average, of Hyalella azteca survived. With Eisenia foetida, the bioaccumulated concentrations of both Pb and Cd were reduced by more than 75%, on average, lower with the addition of birnessite and hydroxyapatite to the contaminated sediments. These results show that the addition of birnessite and hydroxyapatite can reduce the bioavailability of Pb and Cd in contaminated sediments. In addition, the in situ and ex situ performance of birnessite and hydroxyapatite as stabilizing agents can be verified using the toxicity tests with Hyalella azteca and Eisenia foetida, respectively.

• 한국지하수토양환경학회지:지하수토양환경
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• 제18권5호
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• pp.1-6
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• 2013

This study was performed to develop a method for quantitative analysis obtaining the amount of calcium carbonate minerals formed when Ca salts biomimetically reacted with carbon dioxide. There were two methods compared; 1) volumetric calcimeter method that determining the amount of released carbon dioxide after calcium carbonate minerals were acidified by 4N HCl and 2) Thermogravimetry-Differential Thermal Analysis (TG-DTA) adopting differential decomposition temperature breaking-up the structural link within calcium carbonate minerals. The comparisons were made by batch experiment (i.e., biocalcification process) along with control (i.e., nominal concentration of $CaCO_3$ prepared). For the control, TG-DTA took a minor root mean square deviation (RMSD) of 1.1~5.9 mg, whereas volumetric calcimeter exposed a greater RMSD of 28.3 mg. For the biocalcification, the amount of $CaCO_3$ was more precisely obtained for TG-DTA rather than that of volumetric calcimeter. It was decided that TG-DTA was more successfully used for quantitative analysis to observe the amount of calcium carbonate minerals derived from biocalcification.

• 한국토양비료학회지
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• 제48권5호
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• pp.549-555
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• 2015

Objective of this study was to investigate the effect of carbonized biomass from crop residues on chemical properties of soil and soil carbon pools during soybean cultivation. The carbonized biomass was made by field scale mobile pyrolyzer. A pot experiment with soybean in sandy loam soil was conducted for 133 days in a greenhouse, by a completely randomized design with three replications. The treatments consisted of four levels including the control without input and three levels of carbonized biomass inputs of $9.75Mg\;ha^{-1}$, C-1 ; $19.5Mg\;ha^{-1}$, C-2 ; $39Mg\;ha^{-1}$, C-3. Soil samples were collected and analyzed pH, EC, TC, TN, inorganic-N, available phosphorus and exchangeable cations of the soils. Soil pH, Total-N and available phosphorus contents correspondingly increased with increasing the carbonized material input. The contents of soil carbon pools were $19.04Mg\;C\;ha^{-1}$ for C-1, $26.19Mg\;C\;ha^{-1}$ for C-2, $33.62Mg\;C\;ha^{-1}$ for C-3 and $12.01Mg\;C\;ha^{-1}$ for the control at the end of experiment, respectively. Increased contents of soil carbon pools relative to the control were estimated at $7.03Mg\;C\;ha^{-1}$ for C-1, $14.18Mg\;C\;ha^{-1}$ for C-2 and $21.62Mg\;C\;ha^{-1}$ for C-3 at the end of experiment, respectively, indicating that the soil carbon pools were increased with increasing the input rate of the carbonized biomass. Consequently, it seems that the carbonized biomass derived from the agricultural byproducts such as crop residues could increase the soil carbon pools and that the experimental results will be applied to the future study of soil carbon sequestration.

• 한국토양비료학회지
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• 제44권6호
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• pp.1286-1294
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• 2011

This paper reviews the future directions and perspectives on the soil environmental researches in the 21 century. Previously, the principal emphasis of soil environmental researches had put on the enhancement of food and fiber productions. Beside the basic function of soil, however, the societal needs on soil resources in the 21st century have demands for several environmental and social challenges, occurring regionally or globally. Typical global issues with which soil science should deal include food security with increasing agronomic production to meet the exploding world population growth, adaptation and mitigation of climate change, increase of the carbon sequestration, supply of the biomass and bioenergy, securing the water resource and quality, protection of environmental pollution, enhancing the biodiversity and ecosystem health, and developing the sustainable farming/cropping system that improve the use efficiency of water and agricultural resources. These challenges can be solved through the sustainable crop production intensification (SCPI) or plant welfare concept in which soil plays a key role in solving the abovementioned global issues. Through implementation of either concept, soil science can fulfill the goal of the modern agriculture which is the sustainable production of crops while maintaining or enhancing the ecosystem function, quality and health. Therefore, directions of the future soil environmental researches should lie on valuing soil as an ecosystem services, translating research across both temporal and spatial scales, sharing and using data already available for other purposes, incorporating existing and new technologies from other disciplines, collaborating across discipline, and translating soil research into information for stakeholders and end users. Through the outcomes of these approaches, soil can enhance the productivity from the same confined land, increase profitability, conserve natural resource, reduce the negative impact on environment, enhance human nutrition and health, and enhance natural capital and the flow of ecosystem services. Soil is the central dogma, final frontier and new engine for the era of sustainability development in the $21^{st}$ century and thus soil environmental researches should be carried according to this main theme.

• 한국기후변화학회지
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• 제2권3호
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• pp.191-201
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• 2011

본 연구는 전 지구적 문제인 기후변화에 대응하기 위해 하천, 산림 등의 자연 지역과 공원, 녹지 등의 오픈스페이스 등을 녹색기반시설이라는 개념으로 통합하고, 이를 완화와 적응의 관점에서 녹색기반시설이 기후변화에 어떻게 효과적으로 대응할 수 있는지에 대한 연구를 실시하였다. 연구의 결과, 산림, 공원, 녹지, 텃밭, 옥상농장, 자전거로, 보행로 등의 녹색기반시설은 1) 탄소의 저감과 격리, 2) 화석연료 대체, 3) 원자재 대체, 4) 식량 생산, 5) 차량 이동의 감소 등을 통해서 기후변화를 완화시킬 수 있다. 둘째, 하천, 가로수, 저류지, 습지, 사구, 바람길 등의 녹색기반시설은 1) 폭염완화, 2) 물 공급 조절, 3) 강 범람 조절, 4) 해안 범람 조절, 5) 지표수 조절, 6) 토양 침식 감소, 7) 생물종 적응에 도움 등을 통해서 기후변화 적응의 역할을 할 수 있다.

• 터널과지하공간
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• 제29권1호
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• pp.12-29
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• 2019

최근의 이산화탄소 심지층 처분, 인공지열저류층 형성 및 발전, 원유회수증진 사업 등에는 고압의 유체를 주입하는 과정이 수반되고 이들 사업의 안전하고 성공적인 수행을 위해서는 대상 부지 절리 암반의 투수 특성 및 주입압에 의한 역학적 변형에 기인한 변화를 정확하게 평가하는 것이 중요하다. 본 고에서는 절리 암반 수리-역학 특성 파악을 위한 해석적 및 실험적 평가 방법에 대해 검토하였다. 먼저 유체 주입 전 절리 암반 초기 투과 특성 및 수리-역학 특성 평가에 고려해야 할 기술요소를 분석하고 현장 시추공 실험을 통해 이들 수리-역학 특성을 직접 측정하기 위한 최근의 SIMFIP 실험장치의 특징 및 활용방안에 대해서도 검토하였다.

• 한국기후변화학회지
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• 제5권4호
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• pp.339-348
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• 2014

Agro-ecosystem plays an important role in the mitigation of atmospheric $CO_2$ concentration through photosynthesis and soil carbon fixation. The perennial crops have capacity of carbon accumulation because they have lived for years in the same position. Carbon dioxide fixation occurs in the fruit orchard by photosynthesis and soil carbon sequestration. The objectives of this review are to introduce the fruit orchard as a carbon dioxide sink and to summarize the methods that measure $CO_2$ flux in the orchard. There are three difference methods (chamber, biomass, and eddy covariance method) to measure $CO_2$ exchanges on sites. However, there is no standard method suitable for fruit cultivation condition in Korea. Thus the standard method have to be developed in order to exactly estimate the carbon accumulation. In foreign studies, the carbon assessments were conducted in apple, peach, olive, grape orchard and so on. On the other hand the estimation of $CO_2$ exchange was carried out for apple and mandarine orchard in Korea. According to these results, fruit orchard is a $CO_2$ sink even though amount of carbon accumulation is smaller than the forest. To introduce certainly fruit orchard as greenhouse gas sink, long-term monitoring and further study have to be conducted under each planting condition.

• 한국기후변화학회지
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• 제1권2호
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• pp.97-107
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• 2010

산림의 조성 및 경영, 목제품 활용, 전용방지 등을 통한 이산화탄소의 고정 사업은 대기 중의 온실가스 농도를 감소시킬 뿐 아니라, 다양한 생태적, 경제적인 부가 편익을 제공하는 것으로 알려져 있다. 이와 같은 산림 관련 활동을 통하여 획득된 이산화탄소의 순흡수량에 대하여 배출권을 발행하고 거래하는 산림 탄소상쇄 프로그램이 전 세계적으로 운영되고 있다. 산림 탄소상쇄 프로그램은 기업의 사회공헌 활동이나 자발적 배출량 감축, 배출규제의 준수 등에 활용되고 있고, 국내에도 그에 대한 관심이 점차 높아지고 있다. 본 연구에서는 해외의 산림 탄소상쇄 프로그램의 주요 특성들을 비교 분석하여, 프로그램의 구성 요소와 기준, 방안 등에 관하여 고찰하였다. 해외의 산림 탄소상쇄 프로그램의 대상 사업 및 기준, 추가성 분석 방법, 배출권의 발행 형태, 이산화탄소 흡수량의 산정 및 모니터링, 비영속성 관리 방법, 부가 편익에 대한 요구사항 등은 프로그램의 목적과 운영기관, 가치 등에 따라 차이가 있다. 해외의 선진사례들을 참조로 국내 산림 탄소상쇄 사업의 활성화에 기여하면서도 국제적 수준의 품질을 가지는 배출권을 생산하기 위한 프로그램을 개발해야 할 것이고, 이를 위한 방향성과 기본 조건 등을 파악하였다.