• Journal of the Korean Ceramic Society
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• v.38 no.9
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• pp.806-810
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• 2001

$La_{2/3}TiO_3$, $La_2Ti_2O_7$ are used in various parts by dielectric properties. The purpose of the present study is to understand the photoluminescence properties of $Al^{3+}\;and\;Pr^{3+}$ doped perovskite-type $La_{2/3}TiO_3$ and pyrochlore-type $La_2Ti_2O_7$ phosphor, which characterized by the red emission $(^1D_2{\rightarrow}^3H_4)\;of\;Pr^{3+}$ of $Pr^{3+}$ ion. The explanation for the energy transfer and the corresponding critical distance were proposed on the role of Al^3+ ions as energy transfer mediates in perovskite-type $La_{2/3}TiO_3$:Pr phosphor. In order to clarify the distinction of photoluminescence propoerties between the perovskite-type $La_{2/3}TiO_3$ and the pyrochlore $La_2Ti_2O_7$, the trap-involved process and the charge transfer band have been investigated.

• Journal of Nutrition and Health
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• v.38 no.7
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• pp.553-560
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• 2005

The purpose of this study was to examine the lipid peroxidation, plasma antioxidant status and insulin resistance in childhood obesity. To this end, we measured blood lipid profiles, glucose, insulin concentrations, plasma antioxidant vitamins, baseline conjugated diene formation as a measure of LDL oxidation in vivo and TRAP (total radical trapping antioxidant potential) of 93 school children (58 nonobese, 35 overweight-obese). Insulin resistance was estimated by homeostasis model assessment of insulin resistance (HOMA-IR). The overweight-obese children showed significantly higher levels of leptin (p < 0.0001) and triglyceride (p < 0.05) and significantly lower level of plasma Iycopene (p < 0.001) and $\gamma$-tocopherol (p < 0.05) compared with the normal weight children. Furthermore, the levels of TRAP were significantly lower in overweight-obese children (p < 0.05). Significant positive relationships between plasma leptin and conjugated dienes formation (p < 0.005) and inverse relationship between plasma leptin and lipid corrected levels of $\beta$-carotene (p < 0.05), Iycopene (p < 0.05) were observed. Our results showed an increased lipid peroxidation and decreased antioxidant capacity in childhood obesity which could be involved in the atherosclerotic process.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.45 no.7
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• pp.23-31
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• 2008

Experiment results are presented for gate oxide degradation under the constant voltage stress conditions using MOSFETs with 3-nm-thick gate oxides that are treated by deuterium gas. Two kinds of methods, annealing and implantation, are suggested for the effective deuterium incorporation. Annealing process was rather difficult to control the concentration of deuterium. Because the excess deuterium in gate oxide could be a precursor for the wear-out of gate oxide film, we found annealing process did not show improved characteristics in device reliability, compared to conventional process. However, deuterium implantation at the back-end process was effective method for the deuterated gate oxide. Device parameter variations as well as the gate leakage current depend on the deuterium concentration and are improved by low-energy deuterium implantation, compared to those of conventional process. Especially, we found that PMOSFET experienced the high voltage stress shows a giant isotope effect. This is likely because the reaction between "hot" hole and deuterium is involved in the generation of oxide trap.

• Strategy21
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• s.38
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• pp.287-320
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• 2015

On October 27, 2015, USS Lassen(DDG82), a 9,200 ton class Aegis destroyer of the United States Navy, began its operations within 12 nautical miles of Subi Reef, one of the seven artificial islands that China has built and claimed sovereignty over. The maneuver was joined by anti-submarine patrol airplanes such as P-8A and P-3. The White House press secretary mentioned that the President of the United States approved the operation. In response, China announced that it warned the US Navy ship about the 'illegal violation' by sending two destroyers(PLAN Lanzhou and Taizhou). This event represents a close call case where tension between the United States and China in the South China Sea might have been elevated to a conflict between the two navies. Moreover, considering that this happened only one month after Chinese president Xi's state visit to the United States, the event shows that the positions of the two countries have become starkly different to the extent that they are so hard to be reconciled. The United States' position is different from those of Vietnam and the Philippines. Countries like Vietnam and the Philippines have been directly involved in disputes with regard to sovereignty claims across the waters in the South China sea. As for the United States, being a third party in the disputes, it still cannot be a by-stander watching the whole waters in the region fall under the influence of China. Accordingly, the United States maintains that all countries bear the rights of innocent passage and military operations in the Exclusive Economic Zones(EEZ) as stipulated by the United Nations Convention on the Law of the Sea(UNCLOS). In contrast, China claims that, historically, the South China sea has been part of China's territorial waters, and that foreign countries are not allowed to conduct military operations within the waters. It strongly accuses that such military operations are illegal. Against this background, this paper tracks the different positions of the United States and China on the issues regarding the South China sea. It also carefully looks at the possibility that, in the process of dealing with the issues, the two countries may get into an armed conflict as the phrase 'Thucydides Trap' predicts.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.40 no.5
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• pp.60-69
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• 2008

The principal reasons for applying a pigment coating to paper are to improve appearance and printability. The pigment coating provides a surface that is more uniform and more receptive to printing ink than are the uncoated fibers and, in turn, both facilitates the printing process and enhances the graphic reproduction. The improvement in print quality is readily apparent, especially in image areas or when multiple colors are involved. Although pigment coating of paper is to improve the printability, coated paper is not completely free from printing defects. Actually there are a number printing defects that are observed only with the coated papers. Among the printing defects that are commonly observed for coated papers, print mottle during multi-color offset printing is one of the most concerned defects, and it appears not only on solid tone area but also half dot print area. There are four main causes of print mottle ranging from printing inks, dampening solution, paper, and printing press or its operation. These indicates that almost every factors associated with lithographic printing can cause print mottle. Among these variation of paper quality influences most significantly on print mottle problems in multicolor offset printing, and this indicates that paper is most often to be blamed for its product deficiency as far as print mottle problems are concerned. Furthermore, most of the print mottle problems associated with paper is observed when coated papers are printed. Uncoated papers rarely show mottling problems. This indicates that print mottle is the most serious quality problems of coated paper products. Overcoming the print mottle is becoming more difficult because the operating speeds of coating and printing machines are increasing, coating weights are decreasing, and the demands on high-quality printing are increasing. Print mottle in offset printing is caused by (a) nonuniform back trap of ink caused by a nonuniform rate of ink drying, referred as "back trap mottle, and (b) nonuniform absorption of the dampening solution. Furthermore, both forms of print mottle have some relationship to the structure of the coated layer. The surest way of eliminating ink mottling is to eliminate unevenness in the base paper. Coating solutions, often easier to put into practice, should, however, be considered. In this paper the principal factors influencing print mottle of coated papers will be discussed. Especially the importance of base paper roughness, binder migration, even consolidation of coating layers, control of the drying rate, types of binders, etc. will be described.

• Journal of Fisheries and Marine Sciences Education
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• v.10 no.2
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• pp.184-210
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• 1998

The set-net fishing is involved in the trap fishing method that intercepts the fishes migrating along the coast and induces them to be in the bag net stretched in advance. And this fishing also corresponds to the licensed fishing in fisheries law. Though its annual total production of around 50,000 to 70,000 M/T is less than in other fishery section, its price becomes higher because the fishes are sold in the live fish condition. Until recently, the set-net fishing is one of the preferred fisheries on account of its less operation expense and stably operating condition in a long term. In the meantime, the industrialization in Korea having been prospered along coastal area and the over fishing in terms of the powered and larger size fishing boat make the fishing ground environment worse yearly. In addition, its difficulty becomes more worse with issuing fishery product free import in July 1997; accordingly, the strategy for the set-net fishing through business rationalization should be considered. From the discussion of the sort of set-net, general present situation and operating actual state of set-net fishing, the improved methods for business rationalization in the present paper is proposed as follows: 1. to increase the fisheries resource through prevention of the marine contamination and purification of coastal area environment. 2. to save the labour cost through the improved the fishing gear. 3. to improve the fish quality through development of the process technology. 4. to increase the income of fishers through improvement of the distribution channels.

• Journal of Periodontal and Implant Science
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• v.26 no.2
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• pp.448-468
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• 1996

To maintain its functional integrity, bone is continuously remodelled by a process involving resorption by osteoeclasts and formation by osteoblasts, In order to respond to changes in the physical environment or to trauma with the relevant action, this process is strictly regulated by locally synthesized or systemic fators, Prostaglandin $E_2(PGE_2$) is perhaps one of the best studied factors, having been known to affect bone cell function for several decades.$PGE_2$ has both anabolic and catabolic activities. Excess of $PGE_2$ has been implicated in a number of pathological states associated with bone loss in a number of chronic inflammatory conditions such as periodontal disease and rheumatoid arthritis. $PGE_2$ and other arachidonic acid metabolites have been shown to be potent stimulators of osteoclastic bone resorption in organ culture. The anabolic effects of $PGE_2$ were first noticed when an increase in periosteal woven bone formation was seen after the infusion of $PGE_2$ into infants in order to prevent closure of the ductus arteriosus. The cellular basis for the catabolic actions of $PGE_2$ has been well characterized. $PGE_2$increases osteoclast recruitment in bone marrow cell cultures. Also $PGE_2$ has a direct action on osteoclast serving to inhibit activity and can also indirectly activate osteoclast via other cells in the vicinity, presumably osteoblast. The cellular mechanisms for the anabolic actions of $PGE_2$ are not nearly so well understood. The purpose of this paper was to study the effects of $PGE_2$ and dibutyl(DB)cAMP on osteoblastic clone MC3T3El cells and on the generation of osteoclasts from their precursor cells. The effect of $PGE_2$ and DBcAMP on the induction of alkaline phoaphatase(AlP) was investigated in osteoblastic clone MC3T3El cells cultured in medium containing 0.4% fetal bovine serum. $PGE_2$ and DBcAMP stimulated ALP activity and MTT assay in the cells in a dose-dependent manner at concentrations of lO-SOOng/ml. Cycloheximide, protein synthesis inhibitor, inhibited the stimulative effect of $PGE_2$ and DBcAMP on ALP activity in the cells. $PGE_2$also increased the intracellular cAMP content in a dose-dependent fashion with a maximal effect at 500ng/ml. The effect of $PGE_2$ on the generation of osteoclasts was investigated in a coculture system of mouse bone marrow cells with primary osteoblastic cells cultured in media containing 10% fetal bovine serum.After cultures, staining for tartrate-resistant acid phosphatase(TRAP)-marker enzyme of osteoclast was performed. The TRAP(+) multinucleated cells(MNCs), which have 3 or more nuclei, were counted. More TRAP(+) MNCs were formed in coculture system than in control group. $PGE_2(10^{-5}10^{-6}M)$ stimulated the formation of osteoclast cells from mouse bone marrow cells in culture. $PGE_2(10^{-6}M)$ stimulated the formation of osteoclast cells from mouse bone marrow cells in coculture of osteoblastic clone MC3T3E1 cells This results suggest that $PGE_2$ stimulates the differentiation of osteoblasts and generation of osteoclast, and are involved in bone formation, as well as in bone resorption.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.67 no.4
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• pp.211-221
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• 2022

Recently, the demand for the cultivation of upland soil has been increasing, and the rate of conversion of paddy soil into upland soil is also increasing. Theincrease in uneven precipitation due to climate change has resulted in dramatic effects of waterlogging stress on upland crops. Therefore, the present study was conducted to investigate the changes in growth characteristics and the expression patterns of proteins at the two-leaf stage of adzuki beans. The domestic cultivar, Arari (Miryang No. 8), was used to test waterlogging stress. At the two-leaf stage of adzuki beans, plant height slightly decreased androot fresh weight showed significant changes after 3 days of waterlogging treatment. Chlorophyll content was also significantly different after 3 days of waterlogging treatment compared to its content in control plants. Using two-dimensional gel electrophoresis, more than 400 protein spots were identified. Twenty-one differentially expressed proteins from the two-leaf stage were analyzed using linear trap quadrupole-Fourier transform-ion cyclotron resonance mass spectrometry. Of these 21 proteins, 9 were up-regulated and 12 were down-regulated under waterlogging treatment. Protein information resource (https://pir.georgetown.edu/) categories were assigned to all 49 proteins according to their molecular function, cellular component localization, and biological processes. Most of the proteins were found to be involved in the biological process, carbohydrate metabolism and were localized in chloroplasts.