• Title/Summary/Keyword: Indirect reduction

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Cytoprotective Effect by Antioxidant Activity of Codonopsis lanceolata and Platycodon grandiflorum Ethyl Acetate Fraction in Human HepG2 Cells (인간 HepG2 세포에서 더덕 및 도라지 에틸아세테이트 분획물의 항산화 효과에 의한 세포보호 효과)

  • Kim, Soo-Hyun;Choi, Hyun-Jin;Oh, Hyun-Taek;Chung, Mi-Ja;Cui, Cheng-Bi;Ham, Seung-Shi
    • Korean Journal of Food Science and Technology
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    • v.40 no.6
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    • pp.696-701
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    • 2008
  • The objective of this study was to determine whether Codonopsis lanceolata or Platycodon grandiflorum ethyl acetate fraction (CLEA or PGEA) protect cells against sodium nitroprusside (SNP)-induced oxidative stress via the expression of various antioxidant systems. The HepG2 cells exposed for 24 hr to 0.5 mM SNP showed a reduction in the cell viability by an MTT assay. Pretreatment with CLEA and PGEA resulted in an inhibition of SNP-induced cell death. In addition, the effects of CLEA and PGEA on the expression of antioxidant systems via RT-PCR analyses was assessed. The levels of catalase (CAT), glucose-6-phosphate dehydrogenase (G6PD) and metallothionein (MT)-1A mRNA were increased after 24 hr of CLEA exposure. The levels of Mn superoxide dismutase CAT, G6PD, MT-1A, and MT-2A mRNA were increased after PGEA treatment. In conclusion, CLEA and PGEA exert indirect antioxidant effects, perhaps via the induction of a variety of antioxidant systems which, may protect cells against oxidative stress.

Pd/Pd3Fe Alloy Catalyst for Enhancing Hydrogen Production Rate from Formic Acid Decomposition: Density Functional Theory Study (개미산 분해 반응에서 수소 생산성 증대를 위한 Pd/Pd3Fe 합금 촉매: 범밀도 함수 이론 연구)

  • Cho, Jinwon;Han, Jonghee;Yoon, Sung Pil;Nam, Suk Woo;Ham, Hyung Chul
    • Korean Chemical Engineering Research
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    • v.55 no.2
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    • pp.270-274
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    • 2017
  • Formic acid has been known as one of key sources of hydrogen. Among various monometallic catalysts, hydrogen can be efficiently produced on Pd catalyst. However, the catalytic activity of Pd is gradually reduced by the blocking of active sites by CO, which is formed from the unwanted indirect oxidation of formic acid. One of promising solutions to overcome such issue is the design of alloy catalyst by adding other metal into Pd since alloying effect (such as ligand and strain effect) can increase the chance to mitigate CO poisoning issue. In this study, we have investigated formic acid deposition on the bimetallic $Pd/Pd_3Fe$ core-shell nanocatalyst using DFT (density functional theory) calculation. In comparison to Pd catalyst, the activation energy of formic acid dehydrogenation is greatly reduced on $Pd/Pd_3Fe$ catalyst. In order to understand the importance of alloying effects in catalysis, we decoupled the strain effect from ligand effect. We found that both strain effect and ligand effect reduced the binding energy of HCOO by 0.03 eV and 0.29 eV, respectively, compared to the pure Pd case. Our DFT analysis of electronic structure suggested that such decrease of HCOO binding energy is related to the dramatic reduction of density of state near the fermi level.

The Determinants of Attitudes toward Nuclear Power Plant : The Effects of Earthquake Experience and the Reduction in Electricity Charges (원전 유치에 대한 태도의 결정요인: 지진 경험의 영향 및 전기요금 감면 효과)

  • Kim, Jee Young;Oh, Hyungna
    • Environmental and Resource Economics Review
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    • v.27 no.1
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    • pp.139-160
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    • 2018
  • Using survey data of selected 1,349 individuals nationwide in Korea, we measure the influencing factors for the acceptance of nuclear power and estimates the probability of acceptance under several scenarios with different percentages of monetary compensation. Results of panel probit demonstrate that nuclear risk aversion tendency was found to be higher in case of female, younger age, past experience of extreme event such as an earthquake. However, the residents' residency nearby the nuclear power plant was not related to the risk-aversion tendency. In addition, we found that the nuclear acceptance is improved when the monetary compensation rate is increased. Although the policy demand intended to reduce GHG emissions in South Korea, the expansion of nuclear power is not be easy due to the occurrence of recent strong earthquakes because the risk attitude of an individual is influenced by subjective assessments formed through direct and indirect experiences of natural disasters such as an earthquake. Our results suggest that the opposition to construction of nuclear power plant is expected to be further intensified especially when combined with the experiences of threatening earthquakes. As a result, the debate and policy conflicts of nuclear power plants will consistently continue and large social costs are apparent for the acceptance of nuclear power plant.

An Analysis of Sectoral GHG Emission Intensity from Energy Use in Korea (기후변화 협약 대응을 위한 산업별 온실가스 배출 특성 분석)

  • Chung, Whan-Sam;Tohno, Susumu;Shim, Sang-Yul
    • Journal of Korea Technology Innovation Society
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    • v.11 no.2
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    • pp.264-286
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    • 2008
  • In 2006, the share of energy in Korea amounted to 28% from the total import, 97% from overseas dependency, and 83% for the national Greenhouse Gas (GHG) emission in 2004. Thus, from the aspects of economical and environmental policies, an energy analysis is very important, for the industry to cope with the imminent pressure for climate change. However, the estimation of GHG gas emissions due to an energy use is still done in a primitive way, whereby each industry's usage is multiplied by coefficients recommended from international organizations in Korea. At this level, it is impossible to formulate the prevailing logic and policies in face of a new paradigm that seeks to force participation of developing countries through so called post-Kyoto Protocol. In this study, a hybrid energy input-output (E-IO) analysis is conducted on the basis of the input-output(IO) table of 2000 issued by the Bank of Korea in 2003. Furthermore, according to economic sectors, emission of the GHG relative to an energy use is characterized. The analysis is accomplished from four points of view as follows: 1) estimating the GHG emission intensity by 96 sectors, 2) measuring the contribution ratio to GHG emissions by 14 energy sources, 3) calculating the emission factor of 3 GHG compounds, and 4) estimating the total amount of national GHG emission. The total amount estimated in this study is compared with a national official statistical number. The approach could be an appropriate model for the recently spreading concept of a Life Cycle Analysis as it analyzes not only a direct GHG emission from a direct energy use but also an associated emission from an indirect use. We expect this model can provide a form for the basis of a future GHG reduction policy making.

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An Optimal Structure of a Novel Flat Panel Detector to Reduce Scatter Radiation for Clinical Usage: Performance Evaluation with Various Angle of Incident X-ray (산란선 제거를 위한 신개념 간접 평판형 검출기의 임상적용을 위한 최적 구조 : 입사 X선 각도에 따른 성능평가)

  • Yoon, Yongsu
    • Journal of radiological science and technology
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    • v.40 no.4
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    • pp.533-542
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    • 2017
  • In diagnostic radiology, the imaging system has been changed from film/screen to digital system. However, the method for removing scatter radiation such as anti-scatter grid has not kept pace with this change. Therefore, authors have devised the indirect flat panel detector (FPD) system with net-like lead in substrate layer which can remove the scattered radiation. In clinical context, there are many radiographic examinations with angulated incident X-ray. However, our proposed FPD has net-like lead foil so the vertical lead foil to the angulate incident X-ray would have bad effect on its performance. In this study, we identified the effect of vertical/horizontal lead foil component on the novel system's performance and improved the structure of novel system for clinical usage with angulated incident X-ray. Grid exposure factor and image contrast were calculated to investigate various structure of novel system using Monte Carlo simulation software when the incident X-ray was tilted ($0^{\circ}$, $15^{\circ}$, and $30^{\circ}$ from the detector plane). More photons were needed to obtain same image quality in the novel system with vertical lead foil only then the system with horizontal lead foil only. An optimal structure of novel system having different heights of its vertical and horizontal lead foil component showed improved performance compared with the novel system in a previous study. Therefore, the novel system will be useful in a clinical context with the angulated incident X-ray if the height and direction of lead foil in the substrate layer are optimized as the condition of conventional radiography.

A study of Mechanical Properties of Hot Mix Asphalt for Developing of Quiet Pavement (저소음 포장체 개발을 위한 아스팔트 혼합물의 역학적 특성 연구)

  • Lee, Kwan-Ho;Jeong, Tae-Hyun
    • Journal of the Korean Society of Hazard Mitigation
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    • v.9 no.1
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    • pp.49-55
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    • 2009
  • Our domestic economy has been developed very rapidly after 1960's. Also, it is dramatically increasing traffic on road and surround environmental issues. Especially, rapid economic growth has been induced large construction of pavement, and bigger and higher traffic for transportation. These are making air pollution, traffic noise and vibration. The social requirement against the revealed road environment and traffic sound reduction is being demanded. Traffic noise of city zone is showed over the environmental specification more than 57%. In order to overcome these situations, the social attention is being increased. The quiet pavement is the same format of permeable pavement, but is not same for functional performance. In this research, it has been carried out to evaluate the fundamental-mechanical properties of hot mix asphalt for quiet pavement. Especially, couple of laboratory tests are conducted like marshall stability, resilient modulus, indirect tensile test, and compaction energy analysis with gyratory compaction curve. Also, two-layer pavement system has been adopted for developing of quiet pavement. The basic performance of hot mix asphalt of quiet pavement show a satisfaction of specification of hot mix asphalt.

An Empirical Study on the Effect of public Construction Industry by Expansion of New Budget System (계속비 사업 확대로 인한 공공건설사업 파급효과 분석)

  • Kim, Sang-Bum;Lee, Jeong-Dae;Cho, Ji-Hoon
    • Korean Journal of Construction Engineering and Management
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    • v.9 no.3
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    • pp.153-163
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    • 2008
  • Domestic construction industry accounts about 15% of Gross Domestic Product(GDP) and Korean government spends approximately 50 trillion won per year for public infrastructure projects. Effective management of public construction projects would result in cost saving and enhance financial stability of the government. In doing so, the government promoted a new budgeting system, Continual Budget Method(CBM) as a part of public project performance enhancement program published in 1999. This research mainly attempted to investigate and analyze the impact of new budgeting in term of cost and schedule performance. Based on the analysis result of n2 projects. The new budgeting system could save project cost by 9.83y. Due to the saving of indirect costs from reduction. Although limited government budget cannot allow all the projects to be excuted with the new budgeting system, the new budgeting system should be more-widely utilized in the public sector because of its proven benefits from this research.

Burglary Prevention Effect of Target Hardening through Certified Security Products by WDQ Analysis (WDQ분석을 통한 타겟하드닝 CPTED의 침입범죄 예방효과 검증: 안산시 사례 중심으로)

  • Park, Hyeonho;Kim, Kang-Il;Cho, Joon-Tag
    • Korean Security Journal
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    • no.56
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    • pp.9-30
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    • 2018
  • Crime prevention strategies are introduced to reduce the loss caused by crimes, and Target hardening against domestic burglary attacks is broadly accepted as one of such physical security strategies. In terms of business and home security, target hardening is one of the suite of protective measures that are included in crime prevention through environmental design(CPTED). This can include ensuring all doors and windows are sourced and fitted in such a way that they can resist forcible and surreptitious from the attack of intruder. Target hardening with certified security doors, security windows and secure locks are revealed to be much more effective to deter burglary attacks than other security devices, such as CCTV, lightings and alarms which have largely psychological and indirect impact. A pilot program of target hardening utilizing certified security window and locks was carried out in Ansan city, South Korea in 2016. This study is based on the quasi-experimental design of this program for a residential area. The researchers tried to verify the crime displacement effect of the target hardening program and the diffusion effects of crime prevention benefits by analysing the crime statistics. The evaluation utilized WDQ(Weighted Displacement Quotient) technique to analyze whether the crime displacement occurred, compared the crime statistics of the experimental area with that of buffer zone and controlled areas. The result showed that the target hardening program was significantly effective in crime prevention. The number of burglary in the experimental site with target hardening intervention reduced by 100%, although the areas without the intervention showed reduction in the burglary. The crime displacement was not found at all, and the number of burlary at the buffer zone also reduced significantly.

Large Hill-Sachs Lesion Combined with a Rotator Cuff Tear in an Acute Traumatic Anterior Dislocation of the Shoulder in an Elderly Patient Treated with an Allogenic Iliac Tricortical Bone Graft (노인 환자의 급성 외상성 견관절 전방 탈구에서 회전근개 파열과 동반된 거대 Hill-Sachs 병변에 대해 간접 정복 및 지지대 목적의 동종 장골 삼중 피질골 이식을 통한 치료 1예)

  • Hyun, Yoonsuk;Lim, Jinkyu;Baek, Seung-Ha;Park, Jinho;Lee, Seung-Jin
    • Journal of the Korean Orthopaedic Association
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    • v.55 no.2
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    • pp.188-192
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    • 2020
  • An indirect reduction through the bicipital groove and allogenic iliac tricortical bone graft was performed as a treatment for a large Hill-Sachs lesion with a rotator cuff tear in an acute traumatic shoulder joint dislocation in an elderly patient. Six months after surgery, the rotator cuff healing and bone union were confirmed. The patient also showed satisfactory clinical results with 95 points of the American Shoulder and Elbow Surgeons (ASES) shoulder score and active range of motion with 155° flexion, 120° abduction, and 70° external rotation and 30° internal rotation at 90° abduction. The surgical method can be considered for a large Hill-Sachs lesion with rotator cuff tear in an acute traumatic shoulder joint dislocation in elderly patients.

A Study on the GHG Scope 3 Emissions Management Status of the Companies Through CDP Comparative Analysis (CDP 비교 분석을 통한 기업의 GHG Scope 3 배출관리 현황 연구)

  • Sungah Yoon;Hong-Kwan Kim;Young-Woo Chon
    • Journal of the Society of Disaster Information
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    • v.19 no.3
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    • pp.554-561
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    • 2023
  • Purpose: To urge the necessity of disclosure by identifying the relationship between the disclosure status of greenhouse gas emissions from domestic business sites and other indirect emissions to total emissions. Method: The 2021 emission data disclosed in the Carbon Disclosure Project (CDP) was collected by industry and emission category for comparative analysis. Result: The more companies that calculated and disclosed emissions by category within Scope 3, the more active they were in responding to or disclosing evaluation factors other than disclosure of emissions, and those companies were able to obtain higher grades in CDP and ESG evaluations. The number of Scope 3 calculations and disclosures was found to be high. In addition, there was a significant difference in the correlation between the number of Scope 3 disclosures by industry and the share of each scope out of the total in some manufacturing industries. Conclusion: As the number of Scope 3 disclosures, corporate ratings, and total emissions are proportional, it was confirmed that the higher the number of Scope 3 disclosures and GHG emissions, the higher the level of Scope 3 management. Based on Scope 3 emissions calculation and disclosure, effective emissions management and reduction activities are required.