• Advances in environmental research
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• 제8권1호
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• pp.39-54
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• 2019

This paper presents comprehensive scientific details about mangrove soil in Gulf of Kachchh, Gujarat. A total of ten sites were studied during November, 2011 to December, 2014 in order to know the physico-chemical characteristics of mangrove soil. The results indicated that the soil in GoK had silty loam texture. Other physico-chemical parameters ranged as; pH: 7.39-7.61, Bulk Density: 0.30 g/㎤-0.54 g/㎤, Particle Density: 1.26 g/㎤-1.76 g/㎤, Organic Carbon: 0.70%-1.13%, Organic Matter: 1.01%-1.74% and Moisture Content: 33.45%-56.38%. The paper would be useful to the stakeholders, coastal managers and scientific communities to know the mangrove soil conditions of Gulf of Kachchh for management and planning for conservation of mangrove ecosystem.

• Asian-Australasian Journal of Animal Sciences
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• 제22권9호
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• pp.1341-1350
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• 2009

Dietary lipids are rapidly hydrolysed and biohydrogenated in the rumen resulting in meat and milk characterised by a high content of saturated fatty acids and low polyunsaturated fatty acids (PUFA), which contributes to increases in the risk of diseases including cardiovascular disease and cancer. There has been considerable interest in altering the fatty acid composition of ruminant products with the overall aim of improving the long-term health of consumers. Metabolism of dietary lipids in the rumen (lipolysis and biohydrogenation) is a major critical control point in determining the fatty acid composition of ruminant lipids. Our understanding of the pathways involved and metabolically important intermediates has advanced considerably in recent years. Advances in molecular microbial technology based on 16S rRNA genes have helped to further advance our knowledge of the key organisms responsible for ruminal lipid transformation. Attention has focused on ruminal biohydrogenation of lipids in forages, plant oils and oilseeds, fish oil, marine algae and fat supplements as important dietary strategies which impact on fatty acid composition of ruminant lipids. Forages, such as grass and legumes, are rich in omega-3 PUFA and are a useful natural strategy in improving nutritional value of ruminant products. Specifically this review targets two key areas in relation to forages: i) what is the fate of the lipid-rich plant chloroplast in the rumen and ii) the role of the enzyme polyphenol oxidase in red clover as a natural plant-based protection mechanism of dietary lipids in the rumen. The review also addresses major pathways and micro-organisms involved in lipolysis and biohydrogenation.

• Journal of Microbiology and Biotechnology
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• 제24권8호
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• pp.1034-1043
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• 2014

This study determined the effect of light intensity and photoperiod on the dry cell weight and total amount of carotenoids in four isolates of purple non-sulfur bacteria obtained from shaded and exposed microhabitats of a mangrove ecosystem in Kota Kinabalu, Sabah, Malaysia. The initial isolation of the bacteria was carried out using synthetic 112 medium under anaerobic conditions (2.5 klx) at $30{\pm}2^{\circ}C$. On the basis of colony appearance, cell morphology, gram staining, motility test, and 16S rRNA gene sequencing analyses, all four bacteria were identified as Afifella marina. One of the bacterial isolates, designated as Af. marina strain ME, which was extracted from an exposed mud habitat within the mangrove ecosystem, showed the highest yield in dry cell weight ($4.32{\pm}0.03g/l$) as well as total carotenoids ($0.783{\pm}0.002mg/g$ dry cell weight). These values were significantly higher than those for dry cell weight ($3.77{\pm}0.02g/l$) and total carotenoid content ($0.706{\pm}0.008mg/g$) produced by the isolates from shaded habitats. Further analysis of the effect of 10 levels of light intensity on the growth characteristics of Af. marina strain ME showed that the optimum production of dry cell weight and total carotenoids was achieved at different light intensities and incubation periods. The bacterium produced the highest dry cell weight of 4.98 g/l at 3 klx in 72 h incubation, but the carotenoid production of 0.783 mg/g was achieved at 2.5 klx in 48 h incubation. Subsequent analysis of the effect of photoperiod on the production of dry cell weight and total carotenoids at optimum light intensities (3 and 2.5 klx, respectively) revealed that 18 and 24 h were the optimum photoperiods for the production of dry cell weight and total carotenoids, respectively. The unique growth characteristics of the Af. marina strain ME can be exploited for biotechnology applications.

• Journal of Microbiology and Biotechnology
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• 제14권4호
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• pp.885-890
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• 2004

A survey for vesicular-arbuscular mycorrhizae (VAM) occurrence was undertaken in three endangered vegetation sites in the area of Kudankulam atomic power station. Fifteen VAM fungal species were isolated from the root-zone soils of fourteen different plant species. There was a significant correlation observed between the number of spores and of percentage root colonization as exemplified by Phyllanthus niruri and Paspalum vaginatum (450, 95%; 60, 25%). Although VAM species are not known to be strictly site specific, the fact that Acaulospora elegans was observed only in site 1, Glomus pulvinatum in site 2 only, and Gl. intraradices in site 3 only, showed site-specificity in this study. To confirm the infection efficiency, two host plant species in the sites, P. niruri and Eclipta alba, were selected and inoculated in field with three selected VAM fungal spores. Gl. fasciculatum was found to be the most efficient VAM species in percentage root colonization, number of VAM spores, and dry matter content. When the nutrients in roots of P. niruri and E. alba were analyzed, there was higher uptake of K (4.2 and 3.4 times, respectively) and Ca (5.3 and 4.9 times, respectively), the analogues for $^{137}Cs$ and $^{90}Sr$, respectively. From the results, it might be concluded that VAM association helps the plants survive in a disturbed ecosystem and enhances uptake and cycling of radionuclides from the ecosystem.

• 한국환경복원기술학회지
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• 제12권1호
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• pp.82-91
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• 2009

Research was initiated to investigate vegetation characteristics of native ('Pureundle' and 'Sewon') and introduced ('Brilliant' and 'Midnight') Kentucky bluegrass (KB, Poa pratensis L.) varieties by soil-seed applying system on a cut-slope in May 17, 2008. There were no statistic differences observed in soil hardness and soil moisture content while significant differences were observed in surface coverage rate, height and disease occurrence in native and introduced KB varieties. The introduced 'Brilliant' KB was highest in the surface coverage rate from the early period of seeding to August 11, 2008. The surface coverage rate of introduced varieties were high when compared to native varieties in their early growth stage. But native varieties reached to equal surface coverage rate with the introduced varieties when three months after seeding. The height of 'Pureundle' and 'Brilliant' KBs were high compared with Midnight and Sewon KBs. 'Pureundle' and 'Brilliant' KBs were damaged by disease whereas there were no disease occurrence in 'Midnight' and 'Sewon' KBs. Probably, the disease occurrence was close related with the height of KBs not with native and introduced KB varieties. These results indicate that the growth of KB on a cut-slope are statistically affected by varieties in early growth stage of this experiment but reach equal rate between native and introduced KB varieties in three months after seeding. This growth characteristics implies the huge potential of native KB varieties seeding for cut-slope vegetation. Considering that native KB varieties are adapted to a environment and have no risk of causing disturbance to the ecosystem compared to the introduced KB varieties, the use of them as native varieties for a cut-slope vegetation can be increased.

• Nuclear Engineering and Technology
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• 제54권8호
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• pp.3034-3042
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• 2022

The results of radioecological monitoring of the cooling pond Beloyarsk NPP (Russia) have been presented. The influence of waste technological waters of thermal and fast NPP reactors on the content of artificial radionuclides in surface waters and bottom sediments of the Beloyarsk reservoir has been studied. The long-term dynamics of the specific activity of ⁶⁰Co, ⁹⁰Sr, ¹³⁷Cs and ³H in the main components of the freshwater ecosystem at different distances from the source of radionuclide discharge has been estimated. Critical radionuclides (⁶⁰Co and ¹³⁷Cs), routes of their entry and periods of maximum discharge of radioisotopes into the cooling pond have been determined. It is shown that the technology of electricity generation at Beloyarsk NPP, based on fast reactors, has a much smaller effect on the flow of artificial radionuclides into the freshwater ecosystem of the reservoir. During the entire period of monitoring studies, the decrease in the specific activity of radionuclides from NPP origin in surface waters was 4.3-74.5 times, in bottom sediments 10-505 times. The maximum discharge of artificial radionuclides into the reservoir was noted during the period of restoration and decontamination work aimed at eliminating emergencies at the AMB thermal reactors of the first stage of the Beloyarsk NPP.

• Journal of Ecology and Environment
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• 제47권1호
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• pp.1-13
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• 2023

Background: The positive effects of Arctic plants on the soil environment and plant-species co-occurrence patterns are known to be particularly important in physically harsh environments. Although three dominant plants (Cassiope tetragona, Dryas octopetala, and Silene acaulis) are abundant in the Arctic ecosystem at Ny-Ålesund, Svalbard, few studies have examined their occurrence patterns with other species and their buffering effect on soil-temperature and soil-moisture fluctuation. To quantify the plant-species co-occurrence patterns and their positive effects on soil environments, I surveyed the vegetation cover, analyzed the soil-chemical properties (total carbon, total nitrogen, pH, and soil organic matter) from 101 open plots, and measured the daily soil-temperature and soil-moisture content under three dominant plant patches and bare soil. Results: The Cassiope tetragona and Dryas octopetala communities increased the soil-temperature stability; however, the three dominant plant communities did not significantly affect the soil-moisture stability. Non-metric multidimensional scaling separated the sampling sites into three groups based on the different vegetation compositions. The three dominant plants occurred randomly with other species; however, the vegetation composition of two positive co-occurring species pairs (Oxyria digyna-Cerastium acrticum and Luzula confusa-Salix polaris) was examined. The plant species richness did not significantly differ in the three plant communities. Conclusions: The three plant communities showed distinctive vegetation compositions; however, the three dominant plants were randomly and widely distributed throughout the study sites. Although the facilitative effects of the three Arctic plants on increases in the soil-moisture fluctuation and richness were not quantified, this research enables a deeper understanding of plant co-occurrence patterns in Arctic ecosystems and thereby contributes to predicting the shift in vegetation composition and coexistence in response to climate warming. This research highlights the need to better understand plant-plant interactions within tundra communities.

• The Korean Journal of Ecology
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• 제27권1호
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• pp.15-20
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• 2004

With attention to different human activities around Anzali wetland and introduction of different pollutants containing heavy metals into this water ecosystem and absorption and accumulation of heavy metals in shell and muscle of Astacus leptodactylus which is native benthose of Anzali wetland and enjoys food and economic importance; Sampling of waters and sediments from 18 stations and shell and muscle of Astacus leptodactylus from 5 stations had been conducted. After biometric evaluation of Astacus leptodactylus, the chemical analysis of the samples by using international and standard methods and then their heavy metals content was determined by Atomic Absorpotion Spectrophotometer (AAS), model P.U 9400 philips. Result of the analysis stated that; 1) The mean values of Cr, Zn, Pb, Ni, V in Anzali waters were 6.4, 184.5, 28.8, 28.9, 47.1 ($\mu$ gr/lit) respectively, which comparing to the international standards, is not suitable for drinking, but it can be used for agricultural and aquacultural purposes. Even though the concentration of heavy metals in sediments were high, there are in range of acceptable limit for aquatics organisms; 2) Comparatively, the concentration of heavy metals in shell and muscle of Astacus leptodactylus in Anzali wetland (Cr, Zn, Pb, Ni, V in shell were 3.48, 109.3, 14.13, 7.17, 36.2 and in muscle were 2.98, 131.98, 3.12, 4.77, 9.05 ppm respectively) were more than what is determined for Aras dam (in shell were 1.6, 224.3, 7.8, 7.6, 10.3 and in muscle were 1.4, 60.2, 0.45, 2.7, 4.4 mg/kgr respectively); 3) For all samples, concentration of heavy metals in all Astacus leptodactylus in Anzali wetland and Aras dam, was at tolerance level for human consumption; 4) There was no association with significant difference between weight and size of Astacus leptodactylus with absorption and accumulation of heavy metals; but there was a significant association between heavy metals content in water and in sediments, and in sediments, shell and muscle of Astacus leptodactylus in Anzali wetland.

• 한국콘텐츠학회논문지
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• 제19권8호
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• pp.194-204
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• 2019

본 연구의 목적은 디지털콘텐츠 산업과 블록체인 기술의 융합 생태계가 활성화 될 수 있도록 산업 이해관계자들이 상호 활용 가능한 ICO의 핵심요인과 관련된 선행연구를 정리하고, 요인별 중요도를 산출하는 데 있다. 이에 선행연구에서 도출된 핵심요인을 바탕으로 계층구조모델을 구조화하고 AHP 방법론을 활용하여 각 요인의 가중치를 도출하였다. 상위요인에서는 사업(0.422) > 기술(0.172) > 콘텐츠(0.144) > 인력(0.104) > 제도(0.099) > 토큰(0.059) 순으로 중요하게 나타났다. 하위요인에서는 가중치 내림차순으로 실현가능성(0.162) > 법률규제(0.071) > 시장성장성(0.063) 등으로 나타나 각각의 시사점을 기술하였다. 본 연구의 결과는 ICO 발기자뿐만 아니라 투자자 입장에서도 활용될 수 있을 것이며, 산업적 초기 단계에 속하는 블록체인 융합생태계의 학문적 토대를 제공할 수 있을 것이다.

• 한국과학교육학회지
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• 제36권1호
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• pp.29-43
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• 2016

미국과 유럽의 여러 국가에서 과학의 학문 내 핵심 개념을 중심으로 과학 교육과정을 재구성하려는 노력이 시도되고 있으며 그 중 대표적인 변화가 학습발달과정을 이용한 교육과정을 설계하는 것이다. 학습발달과정은 과학의 핵심 개념과 과학적 활동과정을 논리적이며 단계적으로 정교하게 기술한 틀로서 학생이 학습하는 동안 연속적이며 체계적으로 확립되어 가는 이해의 과정을 설명한다. 미국의 차세대과학기준(NGSS)에서 제시한 생명과학 핵심 개념 중 하나인 생태계에 관하여 학습발달과정을 개발하고 개발된 학습발달과정을 평가하고자 하였다. 이를 위해 학습발달과정에 대한 문헌 연구를 통해 개발 절차를 Development, Assessment, Analysis, Amendment의 네 단계로 설정하고 순차적이며 반복적인 과정을 통해 생태계에 관한 학습발달과정을 개발하였다. 그리고 개발된 학습발달과정의 분석 결과 학습 발달과정에 기반을 둔 평가는 학생의 능력을 파악하는데 신뢰할 수 있는 정보를 제공한다는 결론을 도출하였다. 이를 통해 학습발달과정의 개발 과정에 효과적인 방법으로 핵심 성취기준을 이용한 Framework의 개발, OMC 문항 형식과 Rasch 모델을 이용한 평가와 분석 과정을 제안한다. 또한 경험적으로 검증된 학습발달과정을 이용하여 교육 내용, 교육 방법, 교육 평가가 연계된 교육과정 강화 방안을 제안한다. 국내 학습발달과정에 대한 연구가 부족한 시점에 이 연구를 통해 제안된 학습발달과정 개발 절차를 활용하여 학습발달과정의 개발에 수월성을 제공하고, 개발된 학습발달과정의 적용으로 교육과정의 표준과 방향을 제시할 수 있을 것이다.