• 제목/요약/키워드: availability growth

검색결과 542건 처리시간 0.024초

Spatio-temporal Fluctuations of Size-structured Phytoplankton over an Annual Cycle in the Youngsan Lake

  • Song, Eun-Sook;Shin, Yong-Sik
    • 생태와환경
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    • 제41권4호
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    • pp.530-540
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    • 2008
  • The temporal and spatial variations of size-structured phytoplankton dynamics in Youngsan Lake were investigated to explore potential mechanims controlling the dynamics in the Youngsan Lake. Field data were collected monthly from February to October, 2003 at 6 stations along the axis of Youngsan Lake. In this study, phytoplankton (chlorophyll $\alpha$) were categorized into three size classes: micro-size ($>20{\mu}m$), nano-size ($2{\sim}20{\mu}m$) and pico-size ($<20{\mu}m$). Water temperature, light attenuation coefficients, PAR (photosynthetically active radiation) and suspended solids were measured to analyze relationship between physical-chemical properties and size structure of phytoplankton. Phytoplankton blooms developed during March, July and October in the upper region of the main stem whereas small-scaled spring bloom was observed in the lower region. The scales of phytoplankton blooms were higher in the upper regions than the lower region and blooms were predominated by micro-size class in upper region but predominated by nano-size class in lower region. Growth of size-structured phytoplankton appeared to be controlled by rather light availability than temperature-dependant metabolisms in the system. Phytoplankton growth may be also supported by ambient nutrients available in the water column from analyses of chlorophyll $\alpha$ vs. nutrient concentrations including nitrite+nitrate and orthophosphate. Growth of nano-sized phytoplankton alone appeared to be supported by orthophosphate as well as nitrite+nitrate indicating that response of phytoplankton to nutrient inputs may be size-dependent.

Effects of Dietary Supplementation of a Meju, Fermented Soybean Meal, and Aspergillus oryzae for Juvenile Parrot Fish (Oplegnathus fasciatus)

  • Kim, Sung-Sam;Galaz, German Bueno;Pham, Minh Anh;Jang, Ji-Woong;Oh, Dae-Han;Yeo, In-Kyu;Lee, Kyeong-Jun
    • Asian-Australasian Journal of Animal Sciences
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    • 제22권6호
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    • pp.849-856
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    • 2009
  • In this study, dietary supplementations of Korean Meju, fermented soybean meal (F-SBM) by Aspergillus oryzae, and A. oryzae itself were evaluated on growth performance, feed utilization, immune responses and phosphorus availability in juvenile parrot fish, a marine aquaculture fish species. Four isonitrogenous and isocaloric diets were formulated to contain 8% soybean meal (control diet), 4% Meju (50% soybean meal was replaced by Meju), 4% F-SBM (50% soybean meal was replaced by F-SBM), or 0.08% A. oryzae itself. One of the four experimental diets was fed to triplicate groups of fish for 8 weeks. At the end of the feeding trial, no significant differences were found in growth performances and feed utilization. Red blood cell counts in the fish fed the A. oryzae diet were significantly higher than that of fish fed the control diet. The antioxidant activity in Meju diet was significantly higher than that of the control and A. oryzae diets. Fish fed Meju and F-SBM diets showed numerically higher antioxidant activity of serum compared to that of fish fed the control diet, even though it was not significant. Liver superoxide dismutase activity of fish fed the test diets was significantly higher than that of fish fed the control diet. The apparent digestibility coefficients of protein of fish fed all the diets were not significantly different. Phosphorus absorption was numerically increased in fish fed F-SBM and A. oryzae diets compared to that of fish fed the control diet. This study indicates that the fermentation process of soybean meal does not impair growth performance and feed utilization in parrot fish. The fermentation process could enhance the availability of phosphorus in soybean meal and non-specific immune responses of parrot fish.

참돔 (Pagurus major) 치어용 사료에 있어서의 대두박의 이용성과 적정 단백질${\cdot}$에너지 함량 (Availability of Soybean Meal and Suitable Protein${\cdot}$Energy Level in Different Types of Diet of Red Seabream (Pagurus major))

  • 정관식
    • 한국양식학회지
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    • 제5권1호
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    • pp.9-17
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    • 1992
  • 참돔 치어에 있어서의 식물성단백질원의 이용성의 검토와 유효이용을 꾀하기 위하여, 대두박 및 콘글루텐 밀을 배합한 여러 종류의 실험사료를 제작하여 성장, 사료효율 및 어체성분에 미치는 영향을 조사하였다. 그 결과 사료중의 조단백질 및 조지폐함량이 각각 $47{\%}\;,20{\%}$ 구에서 뛰어난 성장 및 사료효율을 나타내었으며, 어분의 $20{\%}$를 대두박으로 대체하여도 성장 및 사료효율에는 아무튼 간제가 없는 것으로 판단되었다. 그리고, 원료대두박의 Ex 처리유무 및 사료의 제조법의 차이에 의한 영양가개선을 인정할 수 없었다.

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Effects of Fermented Cottonseed and Soybean Meal with Phytase Supplementation on Gossypol Degradation, Phosphorus Availability, and Growth Performance of Olive Flounder (Paralichthys olivaceus)

  • Lim, Se-Jin;Kim, Sung-Sam;Pham, Minh-Anh;Song, Jin-Woo;Cha, Ji-Hoon;Kim, Jin-Dong;Kim, Jung-Un;Lee, Kyeong-Jun
    • Fisheries and Aquatic Sciences
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    • 제13권4호
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    • pp.284-293
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    • 2010
  • To reduce anti-nutritional factors in plant protein sources for fish meal replacement in fish feeds, cottonseed and soybean meal (CS) were fermented with Aspergillus oryzae. A feeding trial was conducted to verify the effects of fermented CS (FCS) with phytase supplementation on gossypol detoxification, phosphorus digestibility, antioxidant activity, and growth performance of juvenile olive flounder over 10 weeks. Four diets were formulated to replace 0, 30, or 40% fish meal protein with CS or FCS (designated as CS0, CS30, FCS30P, and FCS40P). Phytase (1,000 FTU/kg) was added to FCS30P and FCS40P. The microbial fermentation significantly increased dietary total polyphenols and consequently led to higher DPPH radical-scavenging activities in fish feed and fish tissue. Dietary and liver gossypol concentrations were dramatically decreased by the fermentation process. Phosphorus digestibility was significantly increased in fish fed the FCS40P diet. However, growth performance decreased in fish fed FCS diets. This study demonstrates that the fermentation process and phytase supplementation can improve the phosphorus availability of plant protein sources in fish. The fermentation of CS by A. oryzae could increase antioxidant activities in feed and fish and effectively degrade toxic gossypol in cottonseed meal.

Effects of Xylanase Supplementation to Wheat-based Diet on the Performance and Nutrient Availability of Broiler Chickens

  • Chiang, Chia-Chun;Yu, Bi;Chiou, Peter Wen-Shyg
    • Asian-Australasian Journal of Animal Sciences
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    • 제18권8호
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    • pp.1141-1146
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    • 2005
  • A trial was conducted to evaluate the level of wheat substituted for corn in a traditional corn-soy diet and the xylanase supplementation effect on the growth performance and nutrient digestion of broiler chickens. This experiment was a randomized design with a 4${\times}$2 factorial arrangement with four levels of wheat substitution and two levels of enzyme inclusion in the diet. Wheat replaced 0, 25, 50 or 100% corn with or without 1 g/kg xylanase supplementation in iso-nitrogenous and iso-calorific experimental diets. The results showed that in the growing period, broilers attained the highest (p<0.05) body weight gain, feed intake, and relative small intestine weight when wheat was substituted at 25% for corn. The relative caecum weight increased (p<0.05) linearly with increasing levels of wheat substitution for corn. However, during the finishing period and entire experimental period from 0 to 6 weeks, no significant difference was shown in the growth performance among all treatments. Xylanase inclusion significantly improved the body weight gain, fat availability (p<0.01) and diet metabolisable energy (p<0.1) but decreased (p<0.05) the relative GI tract weight during the growing period. The digesta viscosity of 6-week old broilers was also decreased (p<0.05). It appears that wheat substituted for corn did not affect the growth performance, nutrient digestion, and the digesta viscosity of chickens. It is acceptable to completely substitute wheat for corn. Xylanase supplementation improved performance.

What Ecosystem Factors Impact the Growth of High-Tech Start-ups in India?

  • Joshi, Kshitija;Satyanarayana, Krishna
    • Asian Journal of Innovation and Policy
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    • 제3권2호
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    • pp.216-244
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    • 2014
  • This paper empirically establishes the role played by the ecosystem related parameters in the emergence and growth of high technology start-up clusters in India. It is mainly based on secondary data from six major start-up hubs in India during the period 2005-2013. Our results throw up several interesting findings. First of all, we find that traditional infrastructure related factors or robust macroeconomic situation in general are not the most important drivers. What really seem to matter are the specific start-up ecosystem related factors - such as the Internet penetration, volume of deal flow, availability of VC funding and a pre-existing critical mass of relevant high technology businesses and skill-sets. Above all, our study points out that high economic growth alone will not automatically lead to spillovers in the form of a vibrant start-up ecosystem. Rather it has to be a product of conscious and concerted policy efforts at all levels that directly address the main challenges faced by the early-stage start-ups.

산지별 맥문동 부탄올분획물의 신경성장인자 유도 효과에 관한 비교 (Comparison of Nerve Growth Factor Induction by Butanol Fraction of Liriope platyphylla and Ophiopogon japonicus)

  • 강동호;김선여
    • 생약학회지
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    • 제39권2호
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    • pp.75-79
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    • 2008
  • Nerve growth factor (NGF) is a protein plays a major role in the development and maintenance of central and peripheral nervous system. Recent data suggest that reduced availability of NGF may play a significant role in the pathogenesis of diabetic $polyneuropathy.^{1)}$ In our previous study, steroidal saponin from Liriope platyphylla showed neurotrophic effect by stimulation of NGF synthesis and activation of tyrosine kinase $signaling.^{2)}$ In this study, we examined the neurotrophic effect of Liriope platyphylla (LP); which was from Mylyang(MYL) and Cheongyang(CHE), and Ophiopogon japonicus (CHI) on in vitro and in vivo model for the comparison of their NGF induction. We quantitatively analyzed spicatoside A in the LP and CHI by HPLC. And we investigated the correlation between the contents of spicatoside A and NGF induction efficacy on PC 12 cells and mouse serum. These results suggest that spicatoside A may enhance NGF induction in animal model.

계분퇴비와 천연무기질 자재를 활용한 고랭지배추 비가림 유기재배 시 시용질소의 이용률과 배추의 생육 (Growth of Korean Kimchi Cabbage and Nitrogen Availability of Fertilizer in Organic Farming with Poultry Manure Compost and Natural Mineral Materials in Highland Rainshelter Cultivation)

  • 김기덕;권영석;유동림;이종남;서종택
    • 한국유기농업학회지
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    • 제21권1호
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    • pp.69-78
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    • 2013
  • 비가림하우스에서 고랭지배추 유기재배 시 시용량 및 토양비옥도에 따른 시용질소의 이용률과 배추의 수량성을 검토하였다. 무비구에서의 구중은 사양토 토양에서 현저히 낮았으며, 비옥도가 낮은 사양토에 비해 비옥도가 높은 식양토에서 높았다. 시비량에 따른 구중의 변화는 비옥도가 높은 식양토에 비해 비옥도가 낮은 사양토에서 더 크게 나타났다. 질소이용률은 토양의 비옥도가 높고, 질소시비량이 많을수록 낮았다. 질소함량 1%의 사양토에서도 계분퇴비 2톤/10a과 표준시비량 수준의 천연무기질자재의 시용으로 질소함량 6%의 식양토의 약 90% 수준의 수량을 나타냈다. 질소, 인산, 및 칼리질 천연광물자원인 구아노, 인광석 및 황산가리고토 등은 친환경 자재로서 균형적 시비를 꾀하는 유기재배에서 널리 활용될 수 있을 것으로 보인다.

Effect of a new phosphorus source, magnesium hydrogen phosphate (MHP) on growth, utilization of phosphorus, and physiological responses in carp Cyprinus carpio

  • Yoon, Tae-Hyun;Won, Seunggun;Lee, Dong-Hoon;Choi, Jung-Woo;Ra, Changsix;Kim, Jeong-Dae
    • Fisheries and Aquatic Sciences
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    • 제19권9호
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    • pp.39.1-39.9
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    • 2016
  • Magnesium hydrogen phosphate (MHP, $MgHPO_4$) recovered from swine manure was prepared as an alternative phosphorus (P) source. Conventional P additives, monocalcium phosphate (MCP), dicalcium phosphate (DCP), and tricalcium phosphate (TCP) were compared with the MHP in terms of growth and P availability by juvenile carp Cyprinus carpio. A basal diet as a negative control was prepared using practical feed ingredients without P supplementation to which four supplemental P sources were added at the level of 2%. Five groups of 450 fish having mean body weight of 6.5 g following 24 h fasting after 2 weeks of adaptation period were randomly distributed into each of 15 tanks (30 fish/tank). Fish were hand-fed to apparent satiety twice a day for 9 weeks. Fish fed the MHP had weight gain (WG), feed conversion ratio (FCR), protein efficiency ratio (PER), and specific growth rate (SGR) comparable to those fed the MCP. Those values of both the MHP and MCP groups were significantly different (p < 0.05) from the other groups. Fish groups fed control and the TCP showed the lowest WG, PER, and SGR and the highest FCR among treatments. No fish were died among treatments during the experimental period. Fish fed control and the TCP showed hematocrit and hemoglobin significantly lower (p < 0.05) than fish fed the MHP. The lowest inorganic P (Pi) in plasma was found in the control group. Even though Pi was not significantly different (p > 0.05) from other phosphate groups, fish fed the MCP and MHP retained higher P in whole body than the other groups. P availability was determined to be 93.2, 62.4, 6.1, and 98.0% for MCP, DCP, TCP, and MHP, respectively. The present results suggested that the MHP recovered from wastewater stream could be used as an alternative P source in carp diet.

Rule of Law, Economic Growth and Shadow Economy in Transition Countries

  • LUONG, Thi Thuy Huong;NGUYEN, Tho Minh;NGUYEN, Thi Anh Nhu
    • The Journal of Asian Finance, Economics and Business
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    • 제7권4호
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    • pp.145-154
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    • 2020
  • The paper aims to investigate the interactions between rule of law, economic growth and the shadow economy in 18 selected transition economies. This study uses annual data over the period 2002-2015 for 18 transition countries to estimate the effects of rule of law and other factors on the size of shadow economy. The transition country group is classified based on International Monetary Fund resources and is selected on the basis of the availability of data. The data examined in this research are derived from the World Bank, Worldwide Governance Indicators project and Working Paper from International Monetary Fund. This study employs GMM method. The results show that the economic growth indicators have negative and statistically significant impact on the shadow economy. Additionally, these results also reveal that in transition countries the size of shadow economy is negatively related to the quality of rule of law. However, the findings of this research also point out that there are positive relationships between inflation, public expenditure and the size of shadow economy. Hence the results from this study suggest that the size of shadow economy could be controlled by improving the effectiveness of rule of law and the growth of economy particularly in transition countries.