• 제목/요약/키워드: A-POC

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제주도 서남방 동중국해에서 하계 입자성부유물 및 표층퇴적물의 C, N 분포 특성 (The Characteristics of suspended particulate matter and surface sediment of C, N in the Northern East China Sea ill summer)

  • 강문규;최영찬
    • 한국해양환경ㆍ에너지학회지
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    • 제6권4호
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    • pp.13-23
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    • 2003
  • Organic carbon and nitrogen contents in suspended particulate matter (SPM) and surface sediments in seawater were measured in the Northern East China Sea in summer. The distribution of particulate organic carbon(POC) and particulate organic nitrogen(PON) were in the ranges of 54~481㎍/ℓ and 6~85㎍/ℓ, respectively, with relatively high level of concentrations in the western and southern sides of the study area. Also, there has been a significantly positive correlation between POC and PON, gradually increasing toward the deeper range of depth. Average C:N ratios of POC and PON of SPM were 6 in study area. The ratios of POC to PON of SPM increased as the range of depth increased, indicating nitrogen decomposes more rapidly than carbon and is considered to be influenced by the input of detritus from surface sediments. The distribution of total organic matter(TOM), total organic carbon(TOC) and total organic nitrogen(TON) in surface sediments were in the ranges of 3.1~9.6%, 0.282~0.635% and 0.022~0.069%, respectively, with relatively low range in the western and northern sides of the study area. The ratio of TOC to TON of surface sediments were in the range of 9.8~17.4(average of 13), strongly indicating the active role of the input from the terrestrial organic pollutants.

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영산강의 유기물 플럭스와 장기변동에 대한 연구 (Long-term Variation and Flux of Organic Carbon in the Human-disturbed Yeongsan River, Korea)

  • 조형찬;조영길
    • 한국해양학회지:바다
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    • 제22권4호
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    • pp.187-198
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    • 2017
  • 영산강의 유기물 농도와 플럭스를 파악하기 위하여 2006~2015년까지 10년 동안 약 2주 간격으로 영본D 지점에서 강물을 채취하여 유기물(DOC, POC)을 분석하였다. DOC 농도는 연평균 $2.49{\sim}4.39mg{\cdot}C/L$ 범위로 연중 중영양상태가 유지되었고, 조류증식 및 강수에 의한 증감에 따라 30.1% (${\sigma}_x/\bar{x}$) 변동하였다. POC는 2006년 $6.68({\pm}2.80)mg{\cdot}C/L$에서 2015년 $0.19({\pm}0.14)mg{\cdot}C/L$로 10년간 점진적으로 무려 97% 감소하였으며, 2011년 보건설을 기점으로 극적인 변화를 보였다. 이는 보에 의한 정체와 거름망 효과에 기인한 것으로서 보건설 전후로 POC와 SPM 관계의 상이함, 보건설 이후 POC와 chlorophyll-a의 관계로부터 POC의 기원 및 조성의 극명한 변화가 유도된 사실을 파악하였다. TOC 농도는 POC 감소효과로 보건설 이후 52.3% 줄었고 POC:DOC 존재형태 비 또한 DOC가 90.9%에 달하는 압도적 우위를 차지하였다. 하구언 배수량을 이용해 계산된 TOC 플럭스는 $2.56{\sim}19.41{\times}10^9g{\cdot}C/yr$ 범위에서 점진적 감소가 뚜렷하였으며, 2011년을 기점으로 전후 5년 평균 $14.54{\times}10^9g{\cdot}C/yr$에서 $5.40{\times}10^9g{\cdot}C/yr$로 62.9% 줄었다. 따라서 보건설 이후 2015년까지 $9.14{\times}10^9g{\cdot}C$, 즉 매년 약 $1.83{\times}10^9g{\cdot}C$의 유기물이 하상에 축적되었을 것으로 추정된다.

탐진강-강진만의 댐하류 열린하구 시스템에서 유기탄소의 조성 및 기원 변화 연구 (Tracing Source and Concentration of Riverine Organic Carbon Transporting from Tamjin River to Gangjin Bay, Korea)

  • 박형근;강동원;신경훈;옥기영
    • 생태와환경
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    • 제50권4호
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    • pp.422-431
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    • 2017
  • 본 연구에서는 상류댐과 열린하구를 가진 소유역에서 하천을 통해 기수역에 유출되는 육상기원 유기탄소의 농도와 발생기원의 시공간적인 분포를 파악하였다. 탐진강과 강진만의 연구결과, 탐진강 상류에 건설된 댐저수지와 강진만 해양에서는 여름 강우 이전에는 일차생산에 의해 저수지 기원, 그리고 해양기원 식물플랑크톤이 유기탄소의 성상과 조성에 영향을 미쳤다. 댐하류 하천에서는 상류댐에서 유래한 물질이, 그리고 금강천이 합류되면서 지류의 영향이 나타났다. 탐진강 하구역은 조석간만에 따라 탐진강에서 공급되는 물질과 바다에서 유입되는 물질, 그리고 국지적인 갈대습지의 영향이 복잡하게 작용하여 DOC와 POC의 농도변화에 영향을 주고 있었다. 특히, 탐진강에서는 대부분의 유기탄소가 DOC 형태로 강하구로 유출되는 반면, 강진만에서는 해양으로부터 들어오는 식물플랑크톤의 영향으로 POC 형태의 공급이 우세하게 나타나는 등 유기탄소의 성상별, 발생기원별 전이가 뚜렷하게 발생하였다. 이와 같은 강과 해양으로 연결하는 하천 유기탄소의 시공간적인 변화연구는 유역의 환경변화에 따른 생태계 물질이동 변화를 평가하고 예측하는 데 활용될 수 있을 것이다.

잇세이 미야케의 디자인 발상과 상업화를 위한 전개과정에 대한 연구 (The Development of Commercialization in the Idea of the Fashion Design, Issey Miyake)

  • 조정미;허은주
    • 한국의류학회지
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    • 제33권1호
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    • pp.80-91
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    • 2009
  • The purpose of this study is to examine how he successfully connected his ideas of fashion design for art with the commerciality without a conflict about for 40 years. It is expected that this study will be a precedent in the aspect of the symmetry between artistry and commercialization in Issey Miyake's works. We will examine Issey Miyake's idea of fashion design and its development for the commercialization since 1970s that he started to give shape to his ideas in the fashion works to exactly commercialize in the market. 1. Re-creation of tradition(a piece of cloth): throughout the 1970s, Miyake continued to experiment with a variety of Eastern design elements. The elements of Japanese or oriental tradition made him to be at the very center of supreme of the world of fashion. He took advantages of his identity, and developed the tradition for mass produce. 2. Design for mass(Pleats Please): Miyake decided to make clothes for the people, not only for the top class of the society. This thought developed the designs for the mass, which were functional, universal for the modem buyer, and accessible to a wide market. He realized his ideal by the medium of pleats, which were made through industrial processes, while he tried variously the aspect of formative of the pleats in the collections. His designs concept is summarized by the industrial product design and anonymous design. 3. Innovation of manufacturing system(A-POC): Miyake in 1999 developed A-POC. A-POC is used modern computers in conjunction with traditional technology. A-POC does not make only a new cloth but also makes a new manufacturing system of clothes.

Filter- and Denuder-Based Organic Carbon Correction for Positive Sampling Artifacts

  • Hwang, InJo;Na, Kwangsam
    • Asian Journal of Atmospheric Environment
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    • 제11권2호
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    • pp.107-113
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    • 2017
  • This study describes (1) the impact of positive sampling artifacts caused by not only a filter-based sampling, but also a denuder-based sampling in the determination of particle-phase organic carbon (POC), (2) the effect of sample flow rate on positive artifacts, and (3) an optimum flow rate that provides a minimized negative sampling artifact for the denuder-based sampling method. To achieve the goals of this study, four different sampling media combinations were employed: (1) Quartz filter-alone (Q-alone), (2) quartz filter behind quartz-fiber filter (QBQ), (3) quartz filter and quartz filter behind Teflon filter (Q-QBT), and (4) quartz filter behind carbon-based denuder (Denuder-Q). The measurement of ambient POC was carried out in an urban area. In addition, to determine gas-phase OC (GOC) removal efficiency of the denuder, a Teflon filter and a quartz filter were deployed upstream and downstream of the denuder, respectively with varying sample flow rates: 5, 10, 20, and 30 LPM. It was found that Q-alone sampling configuration showed a higher POC than QBQ, Q-QBT, and Denuder-Q by 12%, 28%, and 23%, respectively at a sample flow rate of 20 LPM due to no correction for positive artifact caused by adsorption of GOC onto the filter. A lower quantity of GOC was collected from the backup quartz filter on QBQ than that from Q-QBT. This was because GOC was not in equilibrium with that adsorbed on the front quartz filter of QBQ during the sampling period. It is observed that the loss of particle number and mass across the denuder increases with decreasing sample flow rate. The contribution o f positive arti facts to POC decreased with increasing sample flow rate, showing 29%, 25%, and 22% for 10, 20, and 30 LPM, respectively. The 20 LPM turns out to be the optimum sample flow rate for both filter and denuder-based POC sampling.

아산만의 영양염 및 입자성 유기물 (Nutrients and Particulate Organic Matter in Asan Bay)

  • 문창호;박철;이승용
    • 한국수산과학회지
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    • 제26권2호
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    • pp.173-181
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    • 1993
  • 아산만에서 영양염 및 입자성 유기물의 계절적 변화를 조사하였다. 영양염은 8월에 높고 2월에 낮았으며 무기 질소와 인산 인의 원자비는 5월의 24.8을 제외 하고는 Redfield ratio와 유사하였다. 5월에 인산 인을 제외한 다른 영양염들은 염분이 $31.5{\sim}32.0\%0$까지는 염분이 증가할수록 감소하였으나 그 후 다시 증가하여 하구 내에서 영양염 공급이 있음을 시사해주고 있다. 그러나 8월의 조사에서 영양염과 염분이 좋은 역상관 관계는 이 시기에 영양염 공급원이 담수 유입으로 추정된다. chlorophyll a 농도는 5월에 최대이었고 조사시기 동안 Rb/Ra(Rb: fluorescence before acidification, Ra: fluorescence after acidification) 비가 비교적 낮아 조사해역의 식물플랑크톤이 생리적으로 성장하기에 나쁜 환경에 있는 것으로 사료된다. 입자성 유기 규소(PBSi)와 입자성 유기탄소(POC)의 비가 낮고 PBSi/chlorophyll a 비 및 POC/chlorophyll a 비가 상대적으로 높아 아산만에서 저층으로부터 많은 non-living detritus의 공급이 있는 것으로 판단된다.

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GDNF secreted by pre-osteoclasts induces migration of bone marrow mesenchymal stem cells and stimulates osteogenesis

  • Yi, Sol;Kim, Jihee;Lee, Soo Young
    • BMB Reports
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    • 제53권12호
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    • pp.646-651
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    • 2020
  • Bone resorption is linked to bone formation via temporal and spatial coupling within the remodeling cycle. Several lines of evidence point to the critical role of coupling factors derived from pre-osteoclasts (POCs) during the regulation of bone marrow-derived mesenchymal stem cells (BMMSCs). However, the role of glial cell-derived neurotrophic factor (GDNF) in BMMSCs is not completely understood. Herein, we demonstrate the role of POC-derived GDNF in regulating the migration and osteogenic differentiation of BMMSCs. RNA sequencing revealed GDNF upregulation in POCs compared with monocytes/macrophages. Specifically, BMMSC migration was inhibited by a neutralizing antibody against GDNF in pre-osteoclast-conditioned medium (POC-CM), whereas treatment with a recombinant GDNF enhanced migration and osteogenic differentiation. In addition, POC-CM derived from GDNF knock-downed bone marrow macrophages suppressed BMMSC migration and osteogenic differentiation. SPP86, a small molecule inhibitor, inhibits BMMSC migration and osteogenic differentiation by targeting the receptor tyrosine kinase RET, which is recruited by GDNF into the GFRα1 complex. Overall, this study highlights the role of POC-derived GDNF in BMMSC migration and osteogenic differentiation, suggesting that GDNF regulates bone metabolism.

Soil Carbon Dioxide Flux and Organic Carbon in Grassland after Manure and Ammonium Nitrate Application

  • Lee, Do-Kyoung;Doolittle, James J.
    • 한국환경농학회지
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    • 제24권3호
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    • pp.238-244
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    • 2005
  • Fertilization effects on changes in soil $CO_2$ flux and organic C in switchgrass (Panicum virgatum L.) land managed for biomass production were investigated. The mean daily soil $CO_2$ flux in the manure treatment was 5.63 g $CO_2-C\;m^{-2}\;d^{-1}$, and this was significantly higher than the mean value of 3.36 g $CO_2-C\;m^{-2}\;d^{-1}$ in the control. The mean daily $CO_2$ fluxes in N and P fertilizer treatments plots were not different when compared to the value in the control plots. Potentially mineralizable C (PMC), soil microbial biomass C (SMBC), and particulate organic C (POC) were highest at the 0 to 10 cm depth of the manure treatment. Potentially mineralizable C had the strongest correlation with SMBC (r = 0.91) and POC (r = 0.84). There was also a strong correlation between SMBC and POC (r = 0.90). Our results indicated that for the N and P levels studied, fertilization had no impact on temporal changes in soil organic C, but manure application had a significant impact on temporal changes in soil $CO_2$ evolution and active C constituents such as PMC, SMBC, and POC.

동해 방사성탄소동위원소 연구 현황과 전망 (Current Status and Prospects Regarding Radiocarbon Studies in the East Sea)

  • 김민경
    • Ocean and Polar Research
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    • 제44권1호
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    • pp.99-111
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    • 2022
  • Together with the development of measurement techniques, radiocarbon (14C) has been increasingly used as a key tool to investigate carbon cycling and associated biogeochemistry in the ocean. In this paper, the current status of radiocarbon studies in the East Sea (Japan Sea) is reviewed. Previously, spatiotemporal distribution and change of the water masses in the East Sea from 1979 to 1999 were investigated by using the 14C in the dissolved inorganic carbon (DIC). Researches on sinking particulate organic carbon (POC) revealed that POC in the deep ocean has more complex and heterogeneous origins than we expected. In particular, since 2011, Korean researchers have been collecting sinking particle samples for more than 10 years, so it is expected that 14C of POC will provide important information to understand carbon cycling in relation to climate change. Although the quantity of 14C data published in the East Sea is still limited, the importance and the future direction of using 14C to understand the biogeochemical mechanisms of carbon cycling and its role as a carbon reservoir in the East Sea are detailed herein.

탐진강 열린하구에서 탄소물질의 성상별 이동 특성 연구 (A Study on Transport Characteristics of Organic and Inorganic Carbons in the Open Estuary of the Tamjin River, Korea)

  • 박형근;옥기영
    • 환경생물
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    • 제36권4호
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    • pp.665-671
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    • 2018
  • 본 연구는 탐진강 유역의 열린하구 강진만에서 하천과 해양 간의 성상별 탄소물질의 이동 특성을 파악하였다. 탐진강에서는 대부분의 탄소물질이 DOC 형태로 강하구로 유출되며, 하구로 오면서 조간대에 펼쳐진 갈대군락지에서 POC가 국지적으로 공급되고 있었다. 이에 반해 강진만에서는 DIC의 조성비가 탐진강에 비해 높게 나타났으며, 이러한 무기탄소는 주로 해양에서 공급되고 있는 것으로 나타났다. 이러한 결과를 종합해보면, 탐진강 열린하구는 하천과 바다의 영향이 상호 교차하는 지역으로 강에서는 유기탄소의 공급이 바다에서는 무기탄소의 공급이 주로 이루어져서, 탄소물질의 하구순환이 이루어지고 있음을 파악하였다. 이상과 같이 열린하구에서의 탄소조성 변화를 파악함으로써 하천과 하구, 해양 생태계 간의 환경특성에 따른 탄소공급원을 이해할 수 있었으며, 향후 보다 종합적인 연구를 위해 국내의 닫힌 하구와의 비교 자료로 활용될 수 있을 것이다.