• Development and Reproduction
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• v.13 no.4
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• pp.207-215
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• 2009

Numerous factors can affect the activities of hypothalamus-pituitary-gonad (HPG) hormonal axis, resulting in alteration of reproductive capacity or status such as onset of puberty and menopause. Soon after the finding of leptin, a multifunctional hormone secreted from adipocytes, a close relationship between reproduction and body energy balance have been manifested. Ghrelin, another multifunctional hormone from gastrointestinal tract, is an endogenous ligand of growth hormone secretagogue receptor (GHSR), and is thought to be a counterpart of leptin in the regulation of energy homeostasis. As expected, ghrelin can also modulate the reproductive capacity through the modulation of activities of HPG axis. This paper summarizes the current knowledge on the discovery, gene structures, tissue distribution and roles of ghrelin and GHSRs in mammalian reproduction in particular modulation of reproductive hormone secretion in HPG axis. Like POMC gene expression in pituitary gland, preproghrelin gene can generate a complex repertoire of transcripts which further undergo alternative splicing and posttranslational modifications. Concerning the roles of preproghrelin gene products in the control of body physiology except energy homeostasis, limited knowledge is available so far. Several lines of evidence, however, show the interplay of ghrelin between metabolism and reproduction. In rat and human, the distribution of ghrelin receptor GHSRs (GHSR1a and GHSR1b) has been confirmed not only in the hypothalamus and pituitary which were originally postulated as target of ghrelin but also in the testis and ovary. Expression of the preproghrelin gene in the brain and gonads was also verified, suggesting the local role (s) of ghrelin in HPG axis. Ghrelin might play a negative modulator in the secretions of hypothalamic GnRH, pituitary gonadotropins and gonadal steroids though the action on pituitary is still questionable. Recent studies suggest the involvement of ghrelin in regulation of puberty onset and possibly of menopause entry. It is now evident that ghrelin is a crucial hormomal component in 'brain-gut' axis, and is a strong candidate links between metabolism and reproduction. Opposite to that for leptin, ghrelin signaling is likely representing the 'hunger' state of body energy balance and is necessary to avoid the energy investment into reproduction which has not a top priority in maintaining homeostasis. Further researches are needed to gain a deep insight into the more precise action mechanism and role of ghrelin in reproduction, and to guarantee the successful biomedical applications.

• Economic and Environmental Geology
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• v.39 no.2 s.177
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• pp.163-171
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• 2006

This study is the case of groundwater development based on the geometrical fracture model of target area established only through geological fracture mapping technique. A fracture mapping of $9km^2$, eastern Munsan, has been conducted to determine geological and hydrological factors for new water well placement in the Gyeonggi gneiss complex. Geophysical exploration was not applicable because of small restricted area and dense underground utilities at the site. Form line mapping on the basis of foliation orientation and rock type revealed a synform of NS fold axis bearing to the south. An EW geological cross-section passed through the site area shows a F2 synform as a double-wall ice cream spoon shape. Three regional faults of $N20^{\circ}E,\;N30^{\circ}W$, and NS have been dragged into the site to help understand extensional fault paths. The $N20^{\circ}E$ fault with dextral sense is geometrically interpreted as a western fault of two flexural conjugate type-P shear faults in the F2 synformal fold. The NE cross-section reveals that a possible groundwater belt in the western limb of super-posed fold area is formed as a trigonal prism within 100 m depth of the intersectional space between the $N20^{\circ}E$ fault plane and the weakly sheared plane of transposed foliation. Another possible fault for water resource strikes $N40^{\circ}E$. Recommended sites for new water well placement are along the $N20^{\circ}E\;and\;N40^{\circ}E$ faults. As a result of fracture mapping, 145 ton/day of water can be produced at one well along the $N20^{\circ}E$ fault line. Exploration of groundwater in the area is succeeded only using with geological fracture mapping and interpretation of geological cross-section, without any geophysical survey. Intersection of fault generated with the F2 synformal fold and foliation supply space of groundwater reserver.

• Analytical Science and Technology
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• v.23 no.5
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• pp.485-491
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• 2010

A certified reference material (CRM) of KRISS 109-03-SSD was developed for the analysis of hazardous elements in soil. The target elements were As, Cd, Cr, Cu, Hg, Ni, Pb, Zn being regulated by the Soil Environment Conservation Act. Starting material was collected from tailing dump of an unworked tungsten mine at Sangdong (Gangwon-do, Korea). The starting material under-went through a series of fabricating process steps of screening, drying, grinding, sieving, blending, bottling, sterilization and was certified according to the ISO Guide 35. Isotope dilution-inductively coupled mass spectrometry (ID-ICP/MS) and instrumental neutron activation analysis (INAA) were used for the measurement. Homogeneity was tested according to ISO 13528 annex B. The certified values were determined using the results from two different methods or from two independent measurements using a method. Finally, certified values of seven elements of arsenic, cadmium, chromium, copper, lead, nickel and zinc were determined. Mercury did not satisfied the criteria of homogeneity and the result would be provided for information only, together with iron and tungsten. It was also studied, the extractable fraction of elements by aqua regia according to the ISO 11466 protocol being frequently studied for the purpose of environmental monitoring. It was performed as a inter-laboratory study by 6 laboratories of a public institute and universities. Standard deviation among the laboratories was much bigger than the uncertainty of the certified value. The result of inter-laboratory study on the extractable fraction will be provided for information, only.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 2005.06a
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• pp.154-164
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• 2005

Saccharomyces cerevisiae KNU5377 is a thermotolerant strain, which can ferment ethanol from wasted papers and starch at 40$^{\circ}C$ with the almost same rate as at 30$^{\circ}C$. This strain showed alcohol fermentation ability to convert wasted papers 200 g (w/v) to ethanol 8.4% (v/v) at 40$^{\circ}C$, meaning that 8.4% ethanol is acceptable enough to ferment in the industrial economy. As well, all kinds of starch that are using in the industry were converted into ethanol at 40$^{\circ}C$ with the almost same rate as at 30$^{\circ}C$. Hyperthermic cell killing kinetics and differential scanning calorimetry (DSC) revealed that exponentially growing cells of this yeast strain KNU5377 were more thermotolerant than those of S. cerevisiae ATCC24858 used as a control. This intrinsic thermotolernace did not result from the stability of entire cellular components but possibly from that of a particular target. Heat shock induced similar results in whole cell DSC profiles of both strains and the accumulation of trehalose in the cells of both strains, but the trehalose contents in the strain KNU5377 were 2.6 fold higher than that in the control strain. On the contrary to the trehalose level, the neutral trehalase activity in the KNU5377 cells was not changed after the heat shock. This result made a conclusion that though the trehalose may stabilize cellular components, the surplus of trehalose in KNU5377 strain was not essential for stabilization of whole cellular components. A constitutively thermotolerant yeast, S. cerevisiae KNU5377, was compared with a relatively thermosensitive control, S. cerevisiae ATCC24858, by assaying the fluidity and proton ATPase on the plasma membrane. Anisotropic values (r) of both strains were slightly increased by elevating the incubation temperatures from 25$^{\circ}C$ to 37$^{\circ}C$ when they were aerobically cultured for 12 hours in the YPD media, implying the membrane fluidity was decreased. While the temperature was elevated up to 40$^{\circ}C$, the fluidity was not changed in the KNU5377 cell, but rather increased in the control. This result implies that the plasma membrane of the KNU5377 cell can be characterized into the more stabilized state than control. Besides, heat shock decreased the fluidity in the control strain, but not in the KNU5377 strain. This means also there's a stabilization of the plasma membrane in the KNU5377 cell. Furthermore, the proton ATPase assay indicated the KNU5377 cell kept a relatively more stabilized glucose metabolism at high temperature than the control cell. Therefore, the results were concluded that the stabilization of plasma membrane and growth at high temperature for the KNU5377 cell. Genome wide transcription analysis showed that the heat shock responses were very complex and combinatory in the KNU5377 cell. Induced by the heat shock, a number of genes were related with the ubiquitin mediated proteolysis, metallothionein (prevent ROS production from copper), hsp27 (88-fold induced remarkably, preventing the protein aggregation and denaturation), oxidative stress response (to remove the hydrogen peroxide), and etc.

• Clinical and Experimental Pediatrics
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• v.50 no.7
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• pp.678-685
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• 2007

Purpose : Recent reports pointed out that gonadotropin releasing hormone analogue (GnRHa) therapy alone is not so promising for improving adult height in precocious puberty. So, that we studied the growth promoting effect of combined therapy with GnRHa and growth hormone (GH) in early pubertal girls. Methods : Twenty three early pubertal girls ($9.73{\pm}1.59yr$) with predicted adult heights (PAH) below-2 standard deviation score (SDS) were included. They were divided into two groups as follows; Group I before menarche (n=19) and Group II after menarche (n=4). After combined therapy, various growth parameters were compared between two groups and between the before and after therapy. Results : Between the two groups before therapy, chronologic age (CA), growth velocity (GV), body mass index (BMI), target height (TH), PAH and serum insulin-like growth factor binding protein-3 were not different, but BA, height and difference between bone age (BA) and CA were significantly higher and insulin-like growth factor-1 (IGF-1) was marginally higher in group II. After therapy, BA still remained higher in group II, but other parameters were not different. In both groups, after therapy, the difference between BA and CA, the ratio of BA over CA, and GV were significantly decreased, but PAH, height SDS and BMI were significantly increased. Regarding IGF-1 level, a significant increase was noted in group I, but not in group II. Conclusion : With combined therapy of GnRHa and GH, PAH in early pubertal girls might be improved significantly and even approach TH. Among them, those who were before menarche might have greater potential for the height gain than those after menarche in view of IGF-1 changes during therapy.

• Clinical and Experimental Pediatrics
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• v.50 no.2
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• pp.198-204
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• 2007

Purpose : The hope that arresting pubertal developement might increase final adult height has led to an attempt to use GnRH agonist (GnRHa) in children with early puberty and poor growth prognosis. We investigated the growth-promoting effect of GnRH agonists with or without growth hormone (GH) in girls with early puberty and decreased predicted adult height (PAH). Methods : Thirty five girls with advanced bone age and early pubertal signs were randomized for treatment for about 1 year with monthly GnRHa in group 1 (n=18), or with a combination of GH and GnRHa in group 2 (n=17). The following growth parameters were compared between groups, and the difference ($\Delta$) before and after treatment : chronological age (CA), bone age (BA), $\Delta$(BA-CA), height (HT), target height (TH), predicted adult height (PAH), $\Delta$ (TH-PAH), serum insulin-like growth factor (IGF-1) and insulin-like growth factor binding protein (IGFBP-3). Results : Before treatment, BA, TH, PAH Standard deviation scores (SDS), $\Delta$(TH-PAH) were not different between the two groups, but CA was higher in group 2 and $\Delta$(BA-CA) were higher in group 1 (P<0.05). After $1.06{\pm}0.93$ year of treatment, $\Delta$ (BA-CA) decreased and there were significant changes in PAH and $\Delta$ (TH-PAH), especially in group 2 (P<0.05 in group 1, and P<0.001 in group 2). In both groups, IGF-1 and IGFBP-3 were not different before and after treatment, but after treatment, IGF-1 level in group 2 was marginally higher than IGF-1 in group 1 (P<0.1). Conclusion : Compromised predicted adult height in girls with early puberty and advanced bone age was significantly improved with GnRH with/without GH treatment in the short-term period. The addition of GH to GnRHa results in a significant increase in PAH compared to GnRHa alone because GnRHa suppressed growth hormone-IGF-1 axis. For comparison of final adult height, further longitudinal follow-up will be needed.

• The Korean Journal of Pesticide Science
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• v.16 no.4
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• pp.376-382
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• 2012

Environment-friendly agro-materials are are likely to be preferred to chemical insecticides recently. For this reason, many studies are conducted to develop environment-friendly insecticides containing natural materials. This study was also conducted so as to assess ecotoxicity for Emulsifiable concentrate (EC) containing 30% of garlic extract or two plant essential oils (Zanthoxylum, Lemongrass) expected to prevent from pests and be used for agro-materials. Target species used to assess acute toxicity were invertebrate (Daphina magna), fish (Oryzias latipes), honeybee (Apis mellifera L.) and earthworm (Eisenia fetida). The $EC_{50}$ values for of garlic extract 30% EC, Zanthoxylum oil 30% EC and lemongrass oil 30% EC to Daphina magna were 3.3, 10, and $10mg\;L^{-1}$, respectively. The category of garlic extract 30% EC was moderately toxic, while those of Zanthoxylum oil 30% EC and lemongrass oil 30% EC were slightly toxic according to standard of USEPA. $EC_{50}$ for both of Zanthoxylum oil 30% EC and lemongrass oil 30% EC were more than $10mg\;L^{-1}$ then they were considered as slightly toxicity. In case of acute toxicity test to fish, $LC_{50}$ of garlic extract 30% EC was $3.3mg\;L^{-1}$. Zanthoxylum oil 30% EC and lemongrass oil 30% EC indicated $LC_{50}$ > $10mg\;L^{-1}$. Classification of acute toxicity to all test substances was in Korea criteria. Acute contact and oral toxicity test to Honeybee were conducted. As a result, $LD_{50}$ of all test substances were more than 100 a.i. ${\mu}g\;bee^{-1}$ in the acute contact test while $LD_{50}$ of garlic extract 30% EC was 4.4 a.i. ${\mu}g\;bee^{-1}$ and $LD_{50}$ of Zanthoxylum oil 30% EC and lemongrass oil 30% EC were more than 100 a.i. ${\mu}g\;bee^{-1}$. In case of acute toxicity test to earthworm, $LC_{50}$ of garlic extract 30% EC, Zanthoxylum oil 30% EC and lemongrass oil 30% EC were 267, 592, and $430mg\;kg^{-1}$, respectively. In conclusion, if the safety for earthworm is confirmed, these substances are expected to be use for environment-friendly insecticide materials with low risk against ecosystem and contribute to developing environment-friendly agro-materials.

• Proceedings of the KSPS conference
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• 2000.07a
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• pp.235-240
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• 2000

In the age of global communication, more human exchange is extended at the grass-roots level. In the old days, language policy and language planning was based on one nation-state with one language. But high waves of globalizaiton have allowed extended human flow of exchange beyond one's national border on a daily basis. Under such circumstances, homogeneity in Japan may not allow Japanese to speak and communicate only in Japanese and only with Japanese people. In Japan, an advisory report was made to the Ministry of Education in June 1996 about what education should be like in the 21st century. In this report, an introduction of English at public elementary schools was for the first time made. A basic policy of English instruction at the elementary school level was revealed. With this concept, English instruction is not required at the elementary school level but each school has their own choice of introducing English as their curriculum starting April 2002. As Baker, Colin (1996) indicates the age of three as being the threshold diving a child becoming bilingual naturally or by formal instruction. Threre is a movement towards making second language acquisition more naturalistic in an educational setting, developing communicative competence in a more or less formal way. From the lesson of the Canadian immersion success, Genesee (1987) stresses the importance of early language instruction. It is clear that from a psycho-linguistic perspective, most children acquire basic communication skills in their first language apparently effortlessly and without systematic and formal instruction during the first six or seven years of life. This innate capacity diminishes with age, thereby making language learning increasingly difficult. The author, being a returnee, experienced considerable difficulty acquiring L2, and especially achieving native-like competence. There will be many hurdles to conquer until Japanese students are able to reach at least a communicative level in English. It has been mentioned that English is not taught to clear the college entrance examination, but to communicate. However, Japanese college entrance examination still makes students focus more on the grammar-translation method. This is expected to shift to a more communication stressed approach. Japan does not have to aim at becoming an official bilingual country, but at least communicative English should be taught at every level in school Mito College is a small two-year co-ed college in Japan. Students at Mito College are basically notgood at English. It has only one department for business and economics, and English is required for all freshmen. It is necessary for me to make my classes enjoyable and attractive so that students can at least get motivated to learn English. My major target is communicative English so that students may be prepared to use English in various business settings. As an experiment to introduce more communicative English, the author has made the following syllabus design. This program aims at training students speak and enjoy English. 90-minute class (only 190-minute session per week is most common in Japanese colleges) is divided into two: The first half is to train students orally using Graded Direct Method. The latter half uses different materials each time so that students can learn and enjoy English culture and language simultaneously. There are no quizes or examinations in my one-academic year program. However, all students are required to make an original English poem by the end of the spring semester. 2-6 students work together in a group on one poem. Students coming to Mito College, Japan have one of the lowest English levels in all of Japan. However, an attached example of one poem made by a group shows that students can improve their creativity as long as they are kept encouraged. At the end of the fall semester, all students are then required individually to make a 3-minute original English speech. An example of that speech contest will be presented at the Convention in Seoul.

• International Journal of Highway Engineering
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• v.14 no.2
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• pp.63-72
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• 2012

Current analysis method drives an irrationality a road, signal operation and cause confusion of road such as weaving, bottleneck being not including main traffic flow in analysis subject. Therefore, this research develops analysis method of simple grade facilities to grasp target equipment relationship effect as virtue process to grasp effect of simple grade facilities in city and there is the purpose to apply optimum space of analysis intersection. In this paper, get at effect of simple grade facilities in urban area, as well as, develop new analysis method of simple grade facilities and adapt optimal interval of intersection point. New method of this paper reasonably estimated to optimal interval of the traffic flow(diverge area, merge area). As research result, analysis method to present in this research could clarify vague part of existing analysis method and presume reasonable result. Optimal interval of diverge and merge area with facilities was appeared more then 65m from the main line and more then 45m from the frontage road. Meaning of this paper as follow. First, the effect of simple grade facilities estimate. as consider optimal interval of simple grade facilities in urban can plan efficiently operation planning of road and signal in connection with nearby intersection. Second, new method then previous methods. planner of transportation easily access due to run parallel with existing method. Third, new method is contained through traffic volumes. the existing method did not reflect one. and this new method reduce error to the minimum. when analysis of intersection and link. Fourth, using the new method propose improvement plan with road operation and signal operation.

• Korean Journal of Environmental Biology
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• v.25 no.4
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• pp.326-335
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• 2007

This study was conducted to assess the environmental risks of anthracnose resistant transgenic chili peppers with the PepEST gene on non-target organisms in the agroecosystem environments during the chili pepper growing seasons in 2006. We quantitatively collected arthropods assemblages living on leaves and flowers of chili peppers on June 20, July 25, and August 25 by using an insect vacuum collector to compare the patterns of arthropod community structures between non-transgenic chili peppers (nTR, WT512) and anthracnose resistant transgenic chili peppers (TR, line 68). We found the seasonal difference with the highest species richness and Shannon's diversity in July's sampling among the growing seasons (P<0.05) and each sampling season showed the different arthropod community composition. We also found there was no statistical difference between the two types of crops, nTR and TR, at each sampling time (P>0.05). The significance level of arthropod community showed that there were lots of seasonal difference of functional groups as well as taxa but only the herbivore group in the functional groups was significantly different for the types of plants (P<0.05). So, we further examined the herbivore groups to find any potential damage and identified the possibility of herbivorous damage from some herbivores, grasshoppers, aphids and thrips. Although we couldn't find any adverse effects from the environmental risk assessment between the arthropod community structures on two types of plants from our results, we should keep working for the environmental risk assessment because of the herbivorous potential risk possibility.