• Journal of Plant Biotechnology
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• v.6 no.2
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• pp.91-96
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• 2004

The use of liquid-medium-based procedure relative to the solid media led to a 4.5-fold increase in the number of cotyledon-stage embryos. The most efficient system for multiplication and regeneration of somatic embryos was CP6 procedure with the media MSD40/MSD20/MSM6AC/FNL0S3S3GM. However, the rate of regeneration was lower. About 71％ of the embryos with dicotyledon were continued to develop the roots after desiccation treatment and 92％ of the germinated embryos produced shoots in 10 days. Of the four morphologically different types of embryos, dicotyledonous ones showed a high frequency of conversion, while only a few with fused and horn type cotyledon developed shoots. Mature somatic embryos were desiccated in empty petri dishes for 12-72 h. Embryo survival rate was the highest after 12 h of desiccation, but maximal germination was observed at 24 h. After desiccation, they were placed on MS medium without growth regulators for germination. Germinating embryos were transferred to small pots with vermiculite for plant regeneration. The etiolating the plants during the growth was resolved to add 1％ activated charcoal on hormone-free MS medium.

• Molecules and Cells
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• v.43 no.4
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• pp.350-359
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• 2020

Pathogenic aminoacyl-tRNA synthetases (ARSs) are attractive targets for anti-infective agents because their catalytic active sites are different from those of human ARSs. Mupirocin is a topical antibiotic that specifically inhibits bacterial isoleucyl-tRNA synthetase (IleRS), resulting in a block to protein synthesis. Previous studies on Thermus thermophilus IleRS indicated that mupirocin-resistance of eukaryotic IleRS is primarily due to differences in two amino acids, His581 and Leu583, in the active site. However, without a eukaryotic IleRS structure, the structural basis for mupirocin-resistance of eukaryotic IleRS remains elusive. Herein, we determined the crystal structure of Candida albicans IleRS complexed with Ile-AMP at 2.9 A resolution. The largest difference between eukaryotic and prokaryotic IleRS enzymes is closure of the active site pocket by Phe55 in the HIGH loop; Arg410 in the CP core loop; and the second Lys in the KMSKR loop. The Ile-AMP product is lodged in a closed active site, which may restrict its release and thereby enhance catalytic efficiency. The compact active site also prevents the optimal positioning of the 9-hydroxynonanoic acid of mupirocin and plays a critical role in resistance of eukaryotic IleRS to anti-infective agents.

• Korean Journal of Poultry Science
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• v.39 no.4
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• pp.261-267
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• 2012

Different housing systems have considerable influence on performance in poultry production. Therefore, the present study was undertaken to investigate the impact of different housing systems on the performance, bone mineral density and egg yolk fatty acid composition in laying hen. Hy-line brown pullets (n=450) of 12 weeks age were randomly divided into 3 housing systems with 6 replicates of 25 birds in each room. A diet with 2,750 kcal/kg ME and 16.5% CP was assigned to all birds. The pullets provided free access to feed and water. Significantly (P<0.05) higher values for egg production, egg mass and feed conversion efficiency were found in battery cages, however egg weight, egg shell color and breaking strength was remarkably (P<0.05) higher in floor system. The albumin height and Haugh unit were significantly higher (P<0.05) in battery cages which was statistically similar to aviary housing system. The egg yolk fatty acids concentration of linoleic acid and linolenic acids were significantly higher in aviary and in floor system, respectively, however both values were lower in battery cages. Saturated and unsaturated fatty acid content (%) in egg yolk did not influence by any housing systems. Bone mineral density was significantly higher (P<0.05) in floor and aviary housing system than that of battery cage system. It was concluded that in battery cages the egg production and composition maximized, however higher bone mineral density and yolk fatty acids content can be improved in the laying hen reared on floor and aviary housing systems.

• Journal of Power System Engineering
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• v.10 no.2
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• pp.104-110
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• 2006

Corrosion has been around for all of recorded history. Cathodic protection is the electrical solution to the corrosion problem. Corrosion is not exactly a new topic. It has been around since the beginning of time. Corrosion is simply the loss of material resulting from current leaving a metal, following through a medium, and returning to the metal at a different point. Corrosion takes many forms and has various names, such as oxidation, rust, chemical, and bacteria action. Regardless of the agent, all corrosion is the result of electrical current flow. Various methods are used to treat corrosion or to try to prevent ti. Some of these include chemical treatment. coatings, and electrical current. Especially, proper impressed current can stop corrosive action on the protected surface. In this article, we introduce the Impressed Current Cathodic Protection (ICCP) Control and monitoring system developed by ourselves. The ICCP system is composed of a power supply, anode, reference electrode and controller. The main issue is to control the current flow on the desired value such that it is possible to force a metal to be more negative(cathodic) than the natural state. From the this process, we can achieve the cathodic protection. Of course, in the developed system, the necessary functions are possessed, such as remote control, monitoring of system fault detection etc. Some experimental results show the system performance and usefulness.

• Language and Information
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• v.14 no.2
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• pp.71-84
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• 2010

The aim of this paper is to propose that a category P is encapsulated within a functional layer above the lexical layer, just like vP containing a lexical VP. As is well known, the category P has long been in the obscure domain of syntactic studies: Marantz (2001) and den Dikken (2003), for example, argue that P is a lexical category, but Emonds (1985), Grimshaw (1991), and Baker (2003), maintain that the category P is functional and is a closed category without its own intrinsic meaning. On the other hand, Zwart (2005) argues that it does have some meaning. Following the works of Svenonius (2003, 2006, 2007), and the spirit of Rizzi's (1997) split CP hypothesis, we elaborate and develop Svenonius' idea of split-pP analysis with detailed schematic representations of the novel examples in English, Korean, and Chinese in this paper. Unlike Svenonius, however, this paper incorporates KP into pP-Shell, which is a substantial simplification. Furthermore, Chinese Localizers that have long been considered as Postpositions are now under the category of Prepositions. This proposal renders an X-bar theoretic consistency over the categorical status of Chinese phrasal structures. In short, the present analysis accounts for inconsistency found in English complex preposition phrase (Quirk, et al, 1972, 1985), Chinese circumposition phrase (Ernst 1988, Liu, 2002) and Korean postposition phrase in a unified and consistent manner. Furthermore, by proposing a finer-grained phrasal architecture for the category P, the controversial status of the category subsides within this analysis.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.3
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• pp.329-333
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• 2000

Data of 15 multiparous Holstein cows kept at Ibaraki Prefectural Animal Experiment Station were collected from 10 weeks prepartum to 20 weeks postpartum. Cows were assigned randomly to a soybean meal (S8M) diet or a fish meal (FM) diet from 4 weeks before expected calving date to 20 weeks postpartum. Each diet was formulated to contain similar amounts of CP, ADF, and NDF. In the FM diet, 2.5 and 5% of fish meal were supplemented as total mixed rations in prepartum and postpartum periods, respectively. Compared to the SBM diet, undegraded intake protein (UIP) and Met were higher in the FM diet, but Lys was low. Body weight and dry matter intake were not affected by supplemental FM, and dry matter intake increased by 6 weeks postpartum and maintained constant after 7 weeks postpartum. Cows in the FM diet remained high milk production during the experimental period, but milk yield in the SBM diet decreased gradually after 6 weeks postpartum. Supplemental FM increased milk yield and protein yield from 10 to 20 weeks postpartum when FM intake was 1.19 kg/d, although milk protein was not improved. There were no significance differences in fat content and fat yield between FM and SBM diets. Supplemental FM had no effect on plasma glucose and urea-N at parturition and 7 weeks postpartum. Thus, the increased milk and protein yield may be due to the combination of carryover effect of supplemental UIP or Met in FM from 4 weeks prepartum to 10 weeks postpartum and direct effect of supplemental FM.

• Corrosion Science and Technology
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• v.2 no.4
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• pp.202-206
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• 2003

Fusion Bonded Epoxy(FBE) systems have been widely used to protect pipelines for over 30 years. Numerous attempts have so far been made to improve the properties of FBE coatings such as chemical resistance, adhesion, water resistance, cathodic disbondment resistance, impact resistance, and flexibility to protect pipelines at a wet and a high temperature condition. But these attempts have not been successful in reducing some weakness, for instance, in pipeline operating at high temperature due to poor hot water resistance and cathodic protection. The purpose here is to build a basis for getting better corrosion resistance of FBE systems. Cresol-novolac epoxy coating systems were studied compared to bisphenol A type epoxy systems. After the immersion of the film in water at a high temperature for a long period, good adhesion to metal substrate and excellent cathodic disbond resistance were observed in the cresol-novolac epoxy resin systems. It is well known that the adhesion of organic coatings to metal substrate might be decreased due to the disruption of a chemical bond across the film and metal interface induced by water molecules. A high crosslinking density might decrease water permeability and improve cathodic disbonding protection in the coatings. Other factors are studied to understand anti-corrosion mechanism of Cresol-novolac epoxy coatings. In addition, the water absorption rate and the effect of cure temperature on the adhesion and cathodic disbonding resistance ofthe films were studied in different epoxy coatings and the effect of substrate was evaluated. The results of field application are proved that the Cresol-novolac epoxy coating system developed recently is one of the most suitable coatings for protection of pipelines.

• Journal of the Korean Society for Heat Treatment
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• v.18 no.2
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• pp.91-98
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• 2005

Both commercially pure titanium and Ti-6Al-4V alloy have been widely used as biomaterials because of their excellent biocompatibility, corrosion resistance and mechanical properties. However, in recent years, vanadium has been found to cause cytotoxic effects and adverse tissue reactions, while aluminium has been associated with potential neurological disorders. A newly designed ${\alpha}+{\beta}$ type Ti alloy, Ti-10Ta-10Nb alloy showed superior properties to CP Ti and Ti-6Al-4V alloy in the point of biomaterial, and elucidated the future uses as a biomaterial. Microstructural changes of Ti-10Ta-10Nb alloy after hot-rolling, warm-rolling, solution and aging treatment were investigated. According to TEM results, the microstructures after solution treatment were composed of mostly ${\alpha}$ phase with a trace of ${\beta}$ phase due to adding ${\beta}$-phase stabilizer tantalum and niobium. The microstructures after warm-rolling is coarse and elongated ${\alpha}$ phase and hot rolling resulted in very fine ${\alpha}$ widmanst$\ddot{a}$tten. The highest value of hardness was obtained by aging treatment at $400^{\circ}C$ for 20hr in which microstructure consisted of very fine ${\alpha}$ phase in ${\beta}$ matrix.

• Korean Journal of Poultry Science
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• v.27 no.3
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• pp.243-254
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• 2000

The effect of supplemental microbial phytase and non - phytate phosphorus(NPP) levels on layer productivity and nutrient digestibility were conducted in 640 21 weeks - old HyLine brown layer for 12 weeks. Supplemented phytase levels were 0, 300, 500 and 1,000 DPU/kg diet. NPP levels were adjusted with tricalcium phosphate(TCP), which were 0(0.11% NPP), 0.5(0.20), 1.0(0.29) and 1.5%(0.38). ME, CP and Ca levels were maintained at 2,800㎉/kg diet, 16% and 3.5%, respectively. Egg production was increased with phytase compared to without phytase(P〈0.05). Increasement of egg production was higher latter of experimental period. Egg production was not different to phytase levels. Egg production in TCP levels were increased in above 0.5% compared to 0% TCP. Difference of egg production by TCP was higher after 6 week. Especially, egg production to supplemental phytase was higher in 0% TCP. Egg weight was not different to phytase and TCP levels. Egg mass was increased with phytase compared to without phytase, but not difference significantly. There was similar to phytase levels. Egg mass in TCP group was increased in TCP supplementation(P〈0.05). Feed intake was not different in phytase levels, and greater with increasing TCP levels(P〈0.05). Feed conversion was improved with phytase(P〈0.05), and not difference in TCP levels. All of nutrients digestibility tended to improve with phytase, P(P〈0.05), especially. There were not different among phytase levels. The effect of adding phytase was higher in low phosphorus diets compared normal levels. Eggshell breaking strength and eggshell thickness also improved in added phytase(P〈0.05). Tibial ash and P content were slightly increased with phytase, and Ca content also was higher(P〈0.05) compared without phytase. We concluded that supplemental phytase in low phosphorus diet was showed to increase laying performance, feed efficiency, nutrients digestibility, egg quality, and bone development. Phytase supplementation was able to compensate for low NPP diet. We also thought optimum phytase level is 300 DPU, and can decrease NPP supplementation adding phytase in later diet.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.7
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• pp.978-983
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• 2006

Forages from grazing lands comprise conventional feed resources for ruminants in the tropical region. A study was conducted to assess fodder productivity and nutritive potential of deferred forages of six silvopastoral traditional fodder banks in central northwest Tanzania, traditionally known as Ngitiri. The grazing lands were dominated by low quality increaser grass species: Eragrostis spp., Aristida spp., Urochloa spp., Rottboellia exaltata, Cenchrus spp., Cynodon spp. and Chloris spp., and forbs species. The grazing lands had low vegetative basal cover that varied (p<0.05) from 34.7 to 75%, and low forage biomass productivity that varied (p<0.05) from 0.76 to 3.69 tones (t) dry matter (DM)/ha. The forages contained low crude protein (CP) that varied (p<0.05) from 16 to 27 g/kg DM; and had high fibre contents, which varied (p<0.05) from 702-725, 497-573 and 119-225 g/kg DM for neutral detergent fibre (NDF), acid detergent fibre (ADF) and acid detergent lignin (ADL), respectively. The forages were poorly degraded in sacco, and showed low DM degradability (DMD) characteristics of 74, 473 and 576 g/kg DM for DM washing losses (a), slowly degradable feed fraction (b) and potential degradability, (a+b), respectively; and low DMD at 48 h incubation, which varied from 317-345 g/kg DM, and contained low metabolizable energy (ME), (4.2-4.36 MJ/kg DM). The herbage forages would not meet protein and energy requirements for maintenance and production, which could be reflected through low animal productivity. Further work is needed to assess animal productivity (growth, milk, draft force) from conserved forages in traditional fodder banks in the dry season.