• 제목/요약/키워드: Research center

검색결과 60,068건 처리시간 0.081초

금강 유역에서의 기후변화에 대한 유출 영향 분석 (Impact of Climate Change on Runoff Analysis in the Geum River Basin)

  • 안정민;정강영;김경훈;권헌각;양득석;신동석
    • 한국환경과학회지
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    • 제26권5호
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    • pp.549-561
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    • 2017
  • Recently IPCC (International Panel on Climate Change, 2007) pointed out that global warming is a certain ongoing process on the earth, due to which water resources management is becoming one of the most difficult tasks with the frequent occurrences of extreme floods and droughts. In this study we made runoff predictions for several control points in the Geum River by using the watershed runoff model, SSARR (Streamflow Synthesis and Reservoir Regulation Model), with daily RCP 4.5 and RCP 8.5 scenarios for 100 year from 1st Jan 2006 to 31st Dec 2100 at the resolution of 1 km given by Climate Change Information Center. As a result of, the Geum River Basin is predicted to be a constant flow increases, and it showed a variation in the water circulation system. Thus, it was found that the different seasonality occurred.

Effective Control of CH4/H2 Plasma Condition to Synthesize Graphene Nano-walls with Controlled Morphology and Structural Quality

  • Park, Hyun Jae;Shin, Jin-ha;Lee, Kang-il;Choi, Yong Sup;Song, Young Il;Suh, Su Jeong;Jung, Yong Ho
    • Applied Science and Convergence Technology
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    • 제26권6호
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    • pp.179-183
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    • 2017
  • The direct growth method is simplified manufacturing process used to avoid damages and contaminants from the graphene transfer process. In this paper, graphene nano-walls (GNWs) were direct synthesized using electron cyclotron resonance (ECR) plasma by varying the $CH_4/H_2$ gas flow rate on the copper foil at low temperature (without substrate heater). Investigations were carried out of the changes in the morphology and characteristic of GNWs due to the relative intensity of hydrocarbon radical and molecule in the ECR plasma. The results of these investigations were then discussed.

국내 저온용 집열기의 열성능 특성 (Thermal Characteristics of Domestic Solar Collector for Low-Temperature Applications)

  • 김정배;이순명;윤응상;이진국;주문창;이동원;곽희열;백남춘
    • 한국태양에너지학회 논문집
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    • 제27권3호
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    • pp.155-160
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    • 2007
  • This study shows the results on thermal performance test with domestic solar collector for low-temperature applications using KS, then reveals the efficiency difference between KS and EN standard. Using the test results, this study Presents the status of thermal performance with domestic solar collector including flat-plate, single evacuated, and double evacuated (with mirror or U-tube) solar collector.

Evaluation of a moving bed biofilm reactor for simultaneous atrazine, carbon and nutrients removal from aquatic environments: Modeling and optimization

  • Derakhshan, Zahra;Ehrampoush, Mohammad Hassan;Mahvi, Amir Hossein;Dehghani, Mansooreh;Faramarzian, Mohammad;Ghaneian, Mohammad Taghi;Mokhtari, Mehdi;Ebrahimi, Ali Asghar;Fallahzadeh, Hossein
    • Journal of Industrial and Engineering Chemistry
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    • 제67권
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    • pp.219-230
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    • 2018
  • The present study examined a moving bed biofilm reactor (MBBR) bioreactor on a laboratory scale for simultaneous removal of atrazine, organic carbon, and nutrients from wastewater. The maximum removal efficiency of atrazine, chemical oxygen demand (COD), total phosphorus (TP) and total nitrogen (TN) were 83.57%, 90.36%, 90.74% and 87.93 respectively. Increasing salinity up to 40 g/L NaCl in influent flow could inhibit atrazine biodegradation process strongly in the MBBR reactor.Results showed that MBBR is so suitable process for efficiently biodegrading of atrazine and nitrogen removal process was based on the simultaneous nitrification-denitrification (SND) process.

Swarming Differentiation of Vibrio vulnificus Downregulates the Expression of the vvhBA Hemolysin Gene via the LuxS Quorum-Sensing System

  • Kim Moon-Young;Park Ra-Young;Choi Mi-Hwa;Sun Hui-Yu;Kim Choon-Mee;Kim Soo-Young;Rhee Joon-Haeng;Shin Sung-Heui
    • Journal of Microbiology
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    • 제44권2호
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    • pp.226-232
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    • 2006
  • Swarming has proven to be a good in vitro model for bacterial surface adherence and colonization, and the swarming differentiation of a bacterium has been shown to be coupled with changes in the expression of virulence factors associated with its invasiveness, particularly in the early stages of infection. In this study, we attempted to determine whether the expression of vvhA, which encodes for hemolysin/cytolysin (VvhA), is either upregulated or downregulated during the swarming differentiation of V. vulnificus. The insertional inactivation of vvhA itself exerted no detectable effect on the expression of V. vulnificus swarming motility. However, in our lacZ-fused vvhA transcriptional reporter assay, vvhA expression decreased in swarming V. vulnificus as compared to non-swarming or planktonic V. vulnificus. The reduced expression of vvhA in swarming V. vulnificus increased as a result of the deletional inactivation of luxS, a gene associated with quorum sensing. These results show that vvhA expression in swarming V. vulnificus is downregulated via the activity of the LuxS quorum-sensing system, suggesting that VvhA performs no essential role in the invasiveness of V. vulnificus via the adherence to and colonization on the body surfaces required in the early stages of the infection. However, VvhA may playa significant role in the pathophysiological deterioration occurring after swarming V. vulnificus is differentiated into planktonic V. vulnificus.

Induced neural stem cells from human patient-derived fibroblasts attenuate neurodegeneration in Niemann-Pick type C mice

  • Hong, Saetbyul;Lee, Seung-Eun;Kang, Insung;Yang, Jehoon;Kim, Hunnyun;Kim, Jeyun;Kang, Kyung-Sun
    • Journal of Veterinary Science
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    • 제22권1호
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    • pp.7.1-7.13
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    • 2021
  • Background: Niemann-Pick disease type C (NPC) is caused by the mutation of NPC genes, which leads to the abnormal accumulation of unesterified cholesterol and glycolipids in lysosomes. This autosomal recessive disease is characterized by liver dysfunction, hepatosplenomegaly, and progressive neurodegeneration. Recently, the application of induced neural stem cells (iNSCs), converted from fibroblasts using specific transcription factors, to repair degenerated lesions has been considered a novel therapy. Objectives: The therapeutic effects on NPC by human iNSCs generated by our research group have not yet been studied in vivo; in this study, we investigate those effects. Methods: We used an NPC mouse model to efficiently evaluate the therapeutic effect of iNSCs, because neurodegeneration progress is rapid in NPC. In addition, application of human iNSCs from NPC patient-derived fibroblasts in an NPC model in vivo can give insight into the clinical usefulness of iNSC treatment. The iNSCs, generated from NPC patientderived fibroblasts using the SOX2 and HMGA2 reprogramming factors, were transplanted by intracerebral injection into NPC mice. Results: Transplantation of iNSCs showed positive results in survival and body weight change in vivo. Additionally, iNSC-treated mice showed improved learning and memory in behavior test results. Furthermore, through magnetic resonance imaging and histopathological assessments, we observed delayed neurodegeneration in NPC mouse brains. Conclusions: iNSCs converted from patient-derived fibroblasts can become another choice of treatment for neurodegenerative diseases such as NPC.