• 제목/요약/키워드: growth change

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Antarctic Marine Microorganisms and Climate Change: Impacts and Feedbacks

  • Marchant Harvey J.;Davidson Andrew T.;Wright Simon W.
    • Ocean and Polar Research
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    • 제23권4호
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    • pp.401-410
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    • 2001
  • Global climate change will alter many such properties of the Southern Ocean as temperature, circulation, stratification, and sea-ice extent. Such changes are likely to influence the species composition and activity of Antarctic marine microorganisms (protists and bacteria) which playa major role in deter-mining the concentration of atmospheric $CO_2$ and producing precursors of cloud condensation nuclei. Direct impacts of climate change on Antarctic marine microorganisms have been determined for very few species. Increasing water temperature would be expected to result in a southward spread of pelagic cyanobacteria, coccolithophorids and others. Growth rates of many species would be expected to increase slightly but nutrient limitation, especially micronutrients, is likely to result in a negligible increase in biomass. The extent of habitats would be reduced for those organisms presently living close to the upper limit of their thermal tolerance. Increased UVB irradiance is likely to favour the growth of those organisms tolerant of UVB and may change the trophic structure of marine communities. Indirect effects, especially those as a consequence of a diminution of the amount of sea-ice and increased upper ocean stratification, are predicted to lead to a change in species composition and impacts on both trophodynamics and vertical carbon flux.

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Phase change properties of BN doped GeSbTe films

  • 장문형;박성진;박승종;정광식;조만호
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2010년도 제39회 하계학술대회 초록집
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    • pp.226-226
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    • 2010
  • Boron Nitride (BN) doped GeSbTe films were grown by the ion beam sputtering deposition (IBSD). The in-situ sheet resistance data and the x-ray diffraction patterns showed the crystallization is suppressed due to the BN incorporation. The phase change speed in BN doped GeSbTe films were investigated using the static tester equipped with nanosecond pulsed laser. The phase change speed for BN doped GST films become faster than the corresponding values for an undoped GST film. The Johnson-Mehl-Avrami(JMA) plot and Avrami coefficient for laser crystallization showed that the change in growth mode during the laser crystallization is a most important factor for the phase change speed in the BN doped GST films. The JMA results and the atomic force microscopy (AFM) images indicate that the origin of the change in the crystalline growth mode is due to an increase in the number of initial nucleation sites which is produced by the incorporated BN. In addition, the retension properties for the laser writing/erasing are remarkably improved in BN doped GeSbTe films owing to the stability of the incorporated BN.

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How Productive Are Life Insurance Institutions in Malaysia? A Malmquist Approach

  • Masud, Muhammad Mehedi;Rana, Md. Sohel;Mia, Md Aslam;Saifullah, Md. Khaled
    • The Journal of Asian Finance, Economics and Business
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    • 제6권1호
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    • pp.241-248
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    • 2019
  • The purpose of this study is to investigate empirical evidences of productivity of life insurance institutions in Malaysia. Therefore, this study attempts to explore the productivity of the life insurance institutions in Malaysia. The overall findings show that the total factor productivity (TFP) has progressed by 2.5% per year during the study period from 2012 to 2016 in the Malaysian insurance industry. However, TFP change has declined from 2012 to 2015 and observed a negative growth in 2015-16 (3.3%). The highest productivity progress was documented during 2012-13 at a rate of 11.7% while the minimum productivity progress was during 2014-15 (only 0.2%). The results also indicate that the decomposition of TFP found that overall progress could mainly be attributed to technological change (TC). However, technical efficiency change (TEC) and pure technical efficiency change (PTE) have negative impact on TFP. The findings also show that most of the insurance companies have a steady growth. Therefore, this study will contribute new insights for the policy makers and insurance institutions to take appropriate steps in developing relevant policies for increasing productivity of insurance institutions in Malaysia.

풀 핵비등시 단일 기포 성장에 대한 벽면 과열도의 영향에 관한 연구 (Wall Superheat Effect on Single Bubble Growth During Nucleate Boiling at Saturated Pool)

  • 김정배;이한춘;김무환
    • 대한기계학회논문집B
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    • 제29권5호
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    • pp.633-642
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    • 2005
  • Nucleate pool boiling experiments for R11 under a constant wall temperature condition were carried out. A microscale heater array was used for the heating and the measurement of high temporal and spatial resolution by the Wheatstone bridge circuit. Very sensitive heat flow rate data were obtained by the control for the surface condition with high time resolution. The measured heat flow rate shows a discernable peak at the initial growth stage and reaches an almost constant value. In the thermal growth region, bubble shows a growth proportional to $t^{\frac{1}{5}}$. The bubble growth behavior is analyzed with a dimensionless parameter to compare with the previous results in the same scale. As the wall superheat increases, the departure diameter and the departure time increase, and the waiting time decreases. But the asymptotic growth rate is not affected by the wall superheat change. The effect of the wall superheat is resolved into the suggested growth equation. Dimensionless parameters of time and bubble radius characterize the thermal growth behavior well, irrespective of wall condition. The comparison between the result of this study and the previous results shows a good agreement at the thermal growth region. The quantitative analysis for the heat transfer mechanism is conducted with the measured heat flow rate behavior and the bubble growth behavior. The required heat flow rate for the volume change of the observed bubble is about twice as much as the instantaneous heat flow rate supplied from the wall.

기혼여성이 지각한 가족 내 역할 인식 및 부부친밀감과 직무만족도의 관계에서 일-가정양립 인식의 매개효과: 잠재성장모형 및 자기회귀교차지연모형 연구 (Mediating Effects of Work-Family Balance on the Relationship of Role Recognition in the Family, Marital Intimacy and Job Satisfaction of Married Women: Using Latent Growth Curve Modeling and Autoregressive Cross-Lagged Modeling)

  • 한혜림;이지민
    • Human Ecology Research
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    • 제55권3호
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    • pp.263-274
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    • 2017
  • The purposes of this study were to verify the longitudinal mediating effects of work-family balance on the relationship of role recognition in the family, marital intimacy and job satisfaction of married women, and to introduce longitudinal mediating effects by using latent growth curve modeling and autoregressive cross-lagged modeling. The subjects were married women from the third year data of the Korean Longitudinal Survey of Women and Family. Structural equational models were conducted with Amos ver. 21.0. The major findings are as follows. First, the result of the longitudinal mediating effects of latent growth modeling is the rate of change of work-family balance mediated between the rate of change of role recognition in the family and the rate of change of job satisfaction, and the rate of change of work-family balance mediated between the rate of change of marital intimacy and the rate of change of job satisfaction. Second, when using the autoregressive cross-lagged modeling, the more role recognition and marital intimacy of third year were the more work-family balance of fourth year, job satisfaction of fifth year. In both models, work-family balance mediated between role recognition in the family, marital intimacy and job satisfaction. Therefore, through this study, mediating effects of work-family balance can be found that there was a longitudinal effects.

낙동강 물금 지점의 겨울 및 봄철 식물플랑크톤 생물량에 대한 기후변화 영향 (Effect of Climate Change for Diatom Bloom at Winter and Spring Season in Mulgeum Station of the Nakdong River, South Korea)

  • 정승현;박혜경;이혜진;이수형
    • 한국물환경학회지
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    • 제29권2호
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    • pp.155-164
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    • 2013
  • To confirm the relationship between climate change and Stephanodiscus in Mulgeum station of Nakdong River, Korea, this study was conducted. The temperature in crease by climate change was observed in the study site, where the temperature was gradually increased in most seasons, except for summer season. The mass proliferation of Stephanodiscus constantly appeared in every year, especially between November and March, and when Stephanodiscus abundance was above 90% in phytoplankton biomass. Among this period, phytoplankton biomass was high related with water temperature ($r^2$=0.249, P<0.01) than nutrient factors such as nitrogen and phosphorus in the study site. Finally, temperature by climate change can be regarded as the affecting factor for chl. a variation, because temperature was strongly related with water temperature ($r^2$=0.748, P<0.01). From 1997 to 2010, the annual maximum phytoplankton biomass was recorded in the range of temperature from $4.8^{\circ}C$ to $8.4^{\circ}C$, and the range was regarded as the temperature condition for the optimal growth of Stephanodiscus in the study site. On the optimal growth temperature, the trend of monthly average temperature corresponded to the trend of chl. a variation from November to March. In future, the increase of temperature by climate change can prolong Stephanodiscus blooming period in winter and spring seasons.

경제성장과 산업구조 변화에 따른 장기 온실가스 배출량 전망 시나리오 분석 (An Analysis of Long-Term Scenarios for The GHG Emissions Projections Considering Economic Growth and Industrial Structure Change)

  • 권승문;전의찬
    • 한국기후변화학회지
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    • 제7권3호
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    • pp.257-268
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    • 2016
  • Both economic growth and industrial structure have great influence on energy consumption and GHG emissions. This study analyzed long-term scenarios for GHG emissions projections considering economic growth and industry value added change. In consideration of 3 GDP and 3 industry value added outlook, total 9 scenarios were set; 'Assembly Industry Baseline(AI)', 'Assembly KEIT industry(AK)', 'Assembly Advanced Country industry(AA)', 'KDI Industry Baseline(KI)', 'KDI KEIT industry(KK)', 'KDI Advanced Country industry(KA)', 'OECD Industry Baseline(OI)', 'OECD KEIT industry(OK)', and 'OECD Advanced Country industry(OA)' scenarios. In consideration of the GDP increase rate and industry value added outlook, it is estimated that AI scenario's GHG emissions would be 777 million tons of $CO_2eq$ in 2030. On the other hand, in the case of OA scenario, GHG emissions would be 560.2 million tons of $CO_2eq$ in 2030. Differences between AI scenario's and OA scenario's were 216.8 million tons of $CO_2eq$. It can be identified by that GDP and industry value added change have great influence on GHG emissions. In view of the fact that Korea's amount of GHG emission reduction targets in 2030 were 218.6 million tons of $CO_2eq$ that the result of this research could give us valuable insight.

Quality Change in Plug Seedlings of Three Indigenous Medicinal Plants after Short-term Cold Storage

  • Oh, Hye Jin;Park, Ji Eun;Park, Yoo Gyeong;Jeong, Byoung Ryong
    • 한국자원식물학회지
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    • 제26권6호
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    • pp.701-708
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    • 2013
  • To test the quality change of seedlings of three domestic medicinal plants raised in plug trays, a short term storage experiment was conducted. Seedlings were kept in growth chambers for two weeks at 4 or $8^{\circ}C$ temperature combined with 0 or $5{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ PPFD. Quality of glasshouse-raised seedlings was assessed after two weeks of cold storage in the growth chamber and one week of acclimation in the greenhouse. After two weeks of storage in the growth chamber of Perilla frutescens var. acuta Kudo, plant height was the greatest in the treatment $8^{\circ}C$ combined with $0{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ PPFD. Internode length of P. frutescens var. acuta Kudo was the greatest in the treatment of $4^{\circ}C$ combined with $0{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ PPFD. After one week of acclimatization in a glasshouse, the growth and development, such as plant height, internode length and leaf size, were greater in the $8^{\circ}C$ combined with $5{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ PPFD than in the other treatments. After two weeks of storage in the growth chamber of Sophora tonkinensis, plant height increased more in the treatment of $4^{\circ}C$ than $8^{\circ}C$. After one week of acclimatization in a glasshouse, number of leaves did not change in the treatment of $4^{\circ}C$ combined with $0{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ PPFD, but it increased in the other treatments. Leaf width increased more under the dark than light condition. Leaf length did not observably change in any treatments. After two weeks of storage in the growth chamber, plant height of Angelica gigas Nakai was the greatest in the treatment of $8^{\circ}C$. Number of leaves was the greatest in the treatment of $8^{\circ}C$. Leaf growth was greater under dark than light condition. These results suggested that optimal storage environment was $8^{\circ}C$ combined with $5{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ PPFD for P. frutescens var. acuta Kudo, and $4^{\circ}C$ combined with $0{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ PPFD for S. tonkinensis and A. gigas Nakai. Hence, proper combination of temperature and PPFD were necessary for better storage, and acclimatization and growth, thereafter, of the plug seedlings of theses plant species.

고지방식이에서 일반식이로의 전환이 유방암의 성장 및 전이에 미치는 영향 (Effect of dietary changes from high-fat diet to normal diet on breast cancer growth and metastasis)

  • 박성화;정인경;김정현
    • Journal of Nutrition and Health
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    • 제53권4호
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    • pp.369-380
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    • 2020
  • 본 연구에서는 일반식이로의 식이 제한이 고지방식이로 촉진된 유방암의 성장과 전이에 미치는 영향과 그 기전을 알아보았다. 8주간 고지방식이를 섭취시킨 후 유방암을 유방 조직에 이식하거나 꼬리 정맥으로 통해 전이시켰으며, 암 생성 및 전이 후 HFC군은 고지방식이를, DR군은 일반식이로 전환시켜 사육하였다. 본 연구 결과, 원발성 유방암의 경우, HFC군과 DR군의 체중에는 차이가 없었으나 간과 비장, 신장 주변의 지방세포의 무게에서 유의한 차이를 보였다. DR군이 HFC군에 비해 유방암의 개시를 지연시켰으며, 유방암의 성장과 무게를 유의하게 감소시켰다. 일반식이로의 전환에 의한 유방암 성장 억제는 세포 분열 억제와 세포사멸을 조절하는 인자의 발현 감소에 의한 caspase-3의 활성 촉진에 의한 것으로 나타났다. 또한, 식이 제한은 폐로 전이된 유방암의 수를 유의미하게 감소시켰다. 본 실험 결과, 일반식이로의 제한은 고지방식이로 촉진된 유방암의 성장과 전이를 억제하는 효과를 나타내며, 이는 유방암 세포의 성장 억제와 사멸 유도에 의한 것으로 나타났다. 따라서, 유방암의 성장이나전이를 억제하기 위해서는 총 섭취 열량을 조절하고, 지방의 섭취량을 줄이는 균형 잡힌 식이를 섭취하도록 해야 할 것으로 사료된다.