• Nuclear Engineering and Technology
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• v.8 no.3
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• pp.139-143
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• 1976

$^{32}$ P was supplied to the roots of stem-ringed 1-year-old apple trees and 2-year-old citrus trees on which bark segments were isolated above and below the ring. $^{32}$ P was translocated to shoots and leaves although considerable translocation occurred especially in wood and bark tissues. The accumulation of $^{32}$ P in isolated bark segments indicated that the occurrence of these materials in this tissue was via radial translocation from xylem tissue, and that the main upward translocation pathway of $^{32}$ P supplied to roots is through the xylem.

• Economic and Environmental Geology
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• v.41 no.3
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• pp.327-334
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• 2008

Understanding the chemical characteristics of sediments and the nutrient diffusion from sediments to the water body is important in the management of surface water quality. Changes in chemical properties and nutrient concentration of a submerged soil were monitored for 6 months using a microcosm with the thickness of 30cm for upland soil and 15cm of water thickness above the soil. The soil color changed from yellowish red to grey and an oxygenated layer was formed on the soil surface after 5 week flooding. The redox potential and the pH of the pore water in the microcosm decreased during the flooding. The nitrate concentration of the surface water was continuously increased up to $8\;mg\;l^{-1}$ but its phosphate concentration decreased from $2\;mg\;l^{-1}$ to $0.1\;mg\;l^{-1}$ during flooding. However, the concentrations of $NH_4^+$, $PO_4^{3-}$, Fe and Mn in the pore water were increased by the flooding during this period. The increased $NO_3^-$ in the surface water was due to the migration of $NH_4^+$ formed in the soil column and the oxidation to $NO_3^-$ in the surface water. The increased phosphate concentration in the pore water was due to the reductive dissolution of Fe-oxide and Mn-oxide, which scavenged phosphate from the soil solution. The oxygenated layer played a role blocking the migration of phosphate from the pore water to the water body.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2003.02a
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• pp.470-477
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• 2003

토양에 함유된 수분은 식물의 생육뿐만 아니라 식물뿌리의 호흡, 미생물 활성 및 토양의 화학적 상태에 큰 영향을 미친다. 즉, 토양수분은 물에 용해된 무기물과 토양 내의 양분을 녹여 식물 뿌리로 흡수될 수 있도록 이동시키며, 토양 속의 온도를 조절하여 뿌리의 영양분 흡수 능력을 향상시키는 기능을 한다. 또한 토양 속으로 수분이 이동하면서 고갈된 산소를 공급하는 등의 중요한 기능을 하고 있다 (Hillel, 1980). 따라서 토양 내 수분이 과다하거나 부족한 경우 인위적으로 최적 상태의 함수비로 조절하는 물 관리 기술의 중요성이 대두되고 있으며 물 관리 기술의 개발에서 가장 중요한 기술 중의 하나는 토양의 수분 함량을 온라인으로 계측하는 것으로서 관개배구 자동화 기술의 핵심부분이라고 할 수 있다. (중략)

• Journal of Life Science
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• v.12 no.5
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• pp.577-583
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• 2002

The growth kinetics and the production of $\beta$-glucuronidase from transgenic tobacco's suspension culture was investigated in the flask culture and a 2.5 L bubble column reactor. The growth of bubble column reactor was similar to that of flask culture. However, in the bubble column reactor, the production of $\beta$ -glucuronidase reached 2850 U/mg (85-fold higher than that of flask culture). In both case, the production level of $\beta$ -glucuronidase was fluctuated, which was resulted from periodical degradation of the protein. Sucrose is important component in plant culture medium. Twice addition of sucrose in bubble column reactor could not improve cell growth, since other components in a medium were already depleted. However, the addition of sugar decreased cell size, which facilitated the operation of bioreactor. The production of $\beta$ -glucuronidase was continuously increased, however final concentration of $\beta$ -glucuronidase was similar to that without sucrose addition.

• Journal of the East Asian Society of Dietary Life
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• v.9 no.3
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• pp.386-390
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• 1999

소금은 공기나 물과 마찬가지로 사람이 생명을 유지하는 데에 없어서는 안 될 중요한 물질이다. 즉 체액의 삼투압의 균형유지, 신경이나 근육의 활동조절 등을 통하여 생명유지에 중요한 역할을 수행한다. 즉 영양분을 운반하거나 신진 대사를 하거나 노폐물 등 물질이 이동될 때에는 삼투압이 근 구실을 하게 되는데 소금은 이와 같은 체액의 삼투압이 균형을 유지할 수 있도록 하는 것이다. 이외에 소금은 위액의 염산이 되어 살균 작용이나 소화작용을 도와준다. 또한 소금은 간접적으로 적혈구의 생성을 도우며 발한 작용을 통하여 체온의 적절한 유지 기능도 가지고 있다. 이외에 최근 여러 사람이 이용하고 있는 죽염의 기능성 여부에 대하여도 과학적인 규명이 필요한 것으로 보인다.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.5
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• pp.927-938
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• 2000

When microorganism is injected into porous medium such as soils along with appropriate substrate and nutrients, biomass retained in the soil pore. Soil pore size and shape are varied from the initial condition as a result of biofilm formation, which make hydraulic conductivity reduced. In this research, hydraulic conductivity reduction was measured after microorganism are inoculated and cultured with synthetic substrates and nutrients. Biomass-soil mixture was evaluated its applicability to the field condition as an alternative liner material in landfill by measuring hydraulic conductivity change after repetitive freeze-thaw cycles. Resistance of biofilm to chemical solution and degree of biodegradation were measured through column test.

• KSBB Journal
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• v.24 no.1
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• pp.9-16
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• 2009

Chemotaxis is the movement of an organism toward chemical attractant and away from chemical repellents. Several bacteria are known to cometabolically degrade some pollutants and attracted to the pollutants. The chemotactic responses to these compounds influence the efficiency of bioremediation because the first precondition of pollutant degradation is definitely confrontation between microorganisms and pollutants. In this review, we summarize present knowledge of about the chemotactic mechanism to environmental pollutants of Pseudomonas species.

• Proceedings of the Korean Society of Grassland Science Conference
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• 2002.09b
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• pp.103-127
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• 2002

The main problem of the forage-based livestock farming in Germany at the moment is the high yielding cow requiring high energy concentration in feed which can be obtained lot easier with corn and grain than with grass. Therefore milk production tends out of the grassland region and into the forage crop region. Nutrient surplus due to concentrates in milk production in future probably will be limited by the government. The problem can only be solved by using best swards and optimal silage techniques as well as optimisation of manure utilization. Most important steps of sustainable forage production are care of grassland as well as regular resowing, especially of silage meadows. About 40% of Hessian grassland is managed in agri-environmental problems to keep it in use and to protect the natural resources. Selective measures are realized, to solve special problmes of nature and landscape conservation.

• Journal of Life Science
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• v.24 no.2
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• pp.209-217
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• 2014

In a variety of eukaryotic cells, autophagy sequesters a portion of the cytoplasm and targets it to a lytic compartment for degradation in bulk. Autophagy is a dynamic process for degrading cytoplasmic cargoes with various degrees of selectivity, and its activity is tightly regulated in a nutrient- and development-dependent manner. Autophagy research has drawn much attention since autophagy not only is an interesting cell biological phenomenon but also has great potential for medical and agricultural applications. For example, autophagy is associated with cancers and neurodegenerative diseases in human and mammalian cells and is also suggested in remobilization of nutrients during the senescence of plant leaves. In this general review, we describe genetic components of the core autophagic machinery conserved among yeast, animals, and plants and briefly explain how these components are responsible for major steps in plant autophagy. We discuss four common features of autophagic processes: (i) autophagy as a degradation pathway, (ii) the concept of flux in autophagy research, (iii) dependency on developmental and nutritional cues, and (iv) diversity of autophagy, focusing on selective types of autophagy. We also summarize cell biological and physiological functions of plant autophagy. Our intention is to provide a quick guide to autophagy for those who are new to autophagy research.

• Journal of Korean Society of Environmental Engineers
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• v.39 no.7
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• pp.418-425
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• 2017

ZnO nanoparticles (ZnO NPs) are mainly used in semiconductors, solar cells, biosensors, and cosmetics (sunscreen). In this study, we investigated the behavior of ZnO NPs in aquatic and soil environments and their effects on plants (Artemisia annua L.) in hydroponic cultivation. It was confirmed that the ZnO NPs size increased and their dissolution decreased with increasing in pH. Leaching distance of ZnO NPs was less than 2.5 cm, indicating that ZnO NPs had a little potential to leach into deeper soil layers. When ZnO NPs were exposed to plant, the total weights of plants decreased. The effects on the length of root and shoot were not observed. In addition large amount of ZnO NPs were adsorbed on the surface of plant root and didn't translocate into shoot. These results suggest that ZnO NPs block the pores of the root cell wall and decrease the bioavailability of plant nutrients. Therefore it can be speculated that the particles increase in size and settle down in the water environment and may adversely affect the plant growth by firmly adhering to the root surface when the ZnO NPs are exposed to the environment.