• Journal of the Korean association of regional geographers
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• v.8 no.2
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• pp.229-246
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• 2002

This study is a contribution to the geographical understanding of Daejeon Area, playing the role of principal center of Choongchong Province. This area has been urbanized associated with Daejeon Basin, an important natural unit in the middle part of South Korea. In order to understand Daejeon Area in geographer's view, it is necessary to elucidate geomorphological environment of Daejeon Basin and urban expansion pattern associating with it. Our research is converged into dual objectives: one, description and interpretation of basin's landforms; other, urban expansion relating with geomorphological condition. Daejeon's urban expansion has progressed from the border zone of Daejeon Basin toward into the basin, and then vice versa. Relating to rivers valleys in the basin, the urbanization in the basin has been extended from the river valleys of lower order toward those of higher order. Understanding of the geomorphological mosaique of Daejeon basin is an important base for that of urban mosaique of Daejeon City.

• Clinical and Experimental Reproductive Medicine
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• v.23 no.3
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• pp.247-268
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• 1996

It has been known for a long time that gonadotropins and steroid hormones play a pivotal role in a series of reproductive biological phenomena including the maturation of ovarian follicles and oocytes, ovulation and implantation, maintenance of pregnancy and fetal growth & development, parturition and mammary development and lactation. Recent investigations, however, have elucidated that in addition to these classic hormones, multiple growth factors also are involved in these phenomena. Most growth factors in reproductive organs mediate the actions of gonadotropins and steroid hormones or synergize with them in an autocrine/paracrine manner. The insulin-like growth factor(IGF) system, which is one of the most actively investigated areas lately in the reproductive organs, has been found to have important roles in a wide gamut of reproductive phenomena. In the present communication, published literature pertaining to the intrauterine IGF system will be reviewed preceded by general information of the IGF system. The IGF family comprises of IGF-I & IGF-II ligands, two types of IGF receptors and six classes of IGF-binding proteins(IGFBPs) that are known to date. IGF-I and IGF-II peptides, which are structurally homologous to proinsulin, possess the insulin-like activity including the stimulatory effect of glucose and amino acid transport. Besides, IGFs as mitogens stimulate cell division, and also play a role in cellular differentiation and functions in a variety of cell lines. IGFs are expressed mainly in the liver and messenchymal cells, and act on almost all types of tissues in an autocrine/paracrine as well as endocrine mode. There are two types of IGF receptors. Type I IGF receptors, which are tyrosine kinase receptors having high-affinity for IGF-I and IGF-II, mediate almost all the IGF actions that are described above. Type II IGF receptors or IGF-II/mannose-6-phosphate receptors have two distinct binding sites; the IGF-II binding site exhibits a high affinity only for IGF-II. The principal role of the type II IGF receptor is to destroy IGF-II by targeting the ligand to the lysosome. IGFs in biological fluids are mostly bound to IGFBP. IGFBPs, in general, are IGF storage/carrier proteins or modulators of IGF actions; however, as for distinct roles for individual IGFBPs, only limited information is available. IGFBPs inhibit IGF actions under most in vitro situations, seemingly because affinities of IGFBPs for IGFs are greater than those of IGF receptors. How IGF is released from IGFBP to reach IGF receptors is not known; however, various IGFBP protease activities that are present in blood and interstitial fluids are believed to play an important role in the process of IGF release from the IGFBP. According to latest reports, there is evidence that under certain in vitro circumstances, IGFBP-1, -3, -5 have their own biological activities independent of the IGF. This may add another dimension of complexity of the already complicated IGF system. Messenger ribonucleic acids and proteins of the IGF family members are expressed in the uterine tissue and conceptus of the primates, rodents and farm animals to play important roles in growth and development of the uterus and fetus. Expression of the uterine IGF system is regulated by gonadal hormones and local regulatory substances with temporal and spatial specificities. Locally expressed IGFs and IGFBPs act on the uterine tissue in an autocrine/paracrine manner, or are secreted into the uterine lumen to participate in conceptus growth and development. Conceptus also expresses the IGF system beginning from the peri-implantation period. When an IGF family member is expressed in the conceptus, however, is determined by the presence or absence of maternally inherited mRNAs, genetic programming of the conceptus itself and an interaction with the maternal tissue. The site of IGF action also follows temporal (physiological status) and spatial specificities. These facts that expression of the IGF system is temporally and spatially regulated support indirectly a hypothesis that IGFs play a role in conceptus growth and development. Uterine and conceptus-derived IGFs stimulate cell division and differentiation, glucose and amino acid transport, general protein synthesis and the biosynthesis of mammotropic hormones including placental lactogen and prolactin, and also play a role in steroidogenesis. The suggested role for IGFs in conceptus growth and development has been proven by the result of IGF-I, IGF-II or IGF receptor gene disruption(targeting) of murine embryos by the homologous recombination technique. Mice carrying a null mutation for IGF-I and/or IGF-II or type I IGF receptor undergo delayed prenatal and postnatal growth and development with 30-60% normal weights at birth. Moreover, mice lacking the type I IGF receptor or IGF-I plus IGF-II die soon after birth. Intrauterine IGFBPs generally are believed to sequester IGF ligands within the uterus or to play a role of negative regulators of IGF actions by inhibiting IGF binding to cognate receptors. However, when it is taken into account that IGFBP-1 is expressed and secreted in primate uteri in amounts assessedly far exceeding those of local IGFs and that IGFBP-1 is one of the major secretory proteins of the primate decidua, the possibility that this IGFBP may have its own biological activity independent of IGF cannot be excluded. Evidently, elucidating the exact role of each IGFBP is an essential step into understanding the whole IGF system. As such, further research in this area is awaited with a lot of anticipation and attention.

• The Research Journal of the Costume Culture
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• v.5 no.3
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• pp.1-25
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• 1997

The consumers, who are characterized by gathering a wide scope of information and by putting into action immediately, have come to the new group searching for emotion and have played a leading role of market. The characgeristics of consumers are the fact that they have followed the street fashion with no-concept, independent of the trends which the brand has provide for consumers. Therefore it leads to a big gap between the fashion information for enterprises and market formation for consumer class. The principal purpose of this paper is to get closer the distance between the information which is used in merchandise plan and real market for consumers, and to suggest the new direction of information management system in order to enhance the hit rate of merchandise plan. The results are as follows : (1) It is shown the enterprises should divide the information data between fashion information and market information, and understand the mutual relationship of them, and regard the statistical data related on the change of sensitivity and desire in market specialized in attributes of street fashion as the emotional expression\`s view, and manage them by the feedback style. (2) It is shown that enterprises should fully understand the fashion factors in the line of fashion stream with the independence of theme in order to plan the merchandise effectively for market which are specialized in the duality that it has both conservation and innovation at the same time, and detect their change. (3) It is shown that in order to predict exactly, enterprises should reflect the statistical data and the emotional factors in planning the merchandise, bring up the systematic organization, expert system. (4) It is also shown that enterprises should make an effort to pursuit the discriminated brand through the feedback management in which the consumer\`s lasting desires are reflected.

• Tribology and Lubricants
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• v.36 no.1
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• pp.11-17
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• 2020

In manufacturing operations, oil plays a crucial role in reducing friction and wear among interacting surfaces at varying velocities, loads, and temperature. Hydrocarbon oil is considered the origin of lubrication oils. However, this base oil has been limited in its use as it is a principal cause of pollution. This research focuses on identifying a biodegradable base oil lubricant that possesses a stable coefficient of friction and viscosity with temperature. Friction analysis is conducted by employing a pin on a disk tribotester with a fixed load of 10 N at varying sliding speeds ranging from 0.06 m/s to 0.34 m/s. Oil viscosity analysis is perfomed at room temperature by using a rotary viscometer. Tests are performed using canola oil and paraffin oil as lubricants. The results indicate that the viscosity of canola oil is more efficient than paraffin oil. The non-dimensional characteristic number according to the Stribeck curve reveals an elastohydrodynamic lubrication regime with canola oil lubrication. A comparison of both lubricants reveals that, the friction efficiency of canola oil and paraffin oil does not differ considerably. However, the friction in canola oil is observed to decrease more than that in paraffin oil at an elevated sliding speed. The tests confirm that canola oil is potent in minimizing the friction coefficient of SCM440 bodies interacting with one another as well as acted upon by load.

• Journal of Microbiology and Biotechnology
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• v.32 no.10
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• pp.1292-1298
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• 2022

Soil autotrophic bacterial communities play a significant role in the soil carbon (C) cycle in paddy fields, but little is known about how rhizosphere soil microorganisms respond to different long-term (35 years) fertilization practices under double rice cropping ecosystems in southern China. Here, we investigated the variation characteristics of rhizosphere soil RubisCO gene cbbL in the double rice ecosystems of in southern China where such fertilization practices are used. For this experiment we set up the following fertilizer regime: without any fertilizer input as a control (CK), inorganic fertilizer (MF), straw returning (RF), and organic and inorganic fertilizer (OM). We found that abundances of cbbL, 16S rRNA genes and RubisCO activity in rhizosphere soil with OM, RF and MF treatments were significantly higher than that of CK treatment. The abundances of cbbL and 16S rRNA genes in rhizosphere soil with OM treatment were 5.46 and 3.64 times higher than that of CK treatment, respectively. Rhizosphere soil RubisCO activity with OM and RF treatments increased by 50.56 and 45.22%, compared to CK treatment. Shannon and Chao1 indices for rhizosphere soil cbbL libraries with RF and OM treatments increased by 44.28, 28.56, 29.60, and 23.13% compared to CK treatment. Rhizosphere soil cbbL sequences with MF, RF and OM treatments mainly belonged to Variovorax paradoxus, uncultured proteobacterium, Ralstonia pickettii, Thermononospora curvata, and Azoarcus sp.KH33C. Meanwhile, cbbL-carrying bacterial composition was obviously influenced by soil bulk density, rhizosphere soil dissolved organic C, soil organic C, and microbial biomass C contents. Fertilizer practices were the principal factor influencing rhizosphere soil cbbL-carrying bacterial communities. These results showed that rhizosphere soil autotrophic bacterial communities were significantly changed under conditions of different long-term fertilization practices Therefore, increasing rhizosphere soil autotrophic bacteria community with crop residue and organic manure practices was found to be beneficial for management of double rice ecosystems in southern China.

• The Bulletin of The Korean Astronomical Society
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• v.44 no.2
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• pp.68.1-68.1
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• 2019

Turbulence plays a crucial role in controlling star formation as it produces density fluctuation as well as non-thermal pressure against gravity. Therefore, turbulence controls the mode and tempo of star formation. However, despite a plenty of previous studies, the properties of turbulence remain poorly understood. As part of the Taeduk Radio Astronomy Observatory (TRAO) Key Science Program (KSP), "mapping Turbulent properties In star-forming MolEcular clouds down to the Sonic scale (TIMES; PI: Jeong-Eun Lee)", we mapped the Orion A and the Ophiuchus clouds, in three sets of lines (13CO 1-0/C18O 1-0, HCN 1-0/HCO+ 1-0, and CS 2-1/N2H+ 1-0) with a high-velocity resolution (~0.1 km/s) using the TRAO 14-m telescope. The mean Trms for the observed maps are less than 0.25 K, and all these maps show uniform Trms values throughout the observed area. These homogeneous and high signal-to-noise ratio data provide the best chance to probe the nature of turbulence in two different star-forming clouds, the Orion A and Ophiuchus clouds. We present comparisons between the line intensities of different molecular tracers as well as the results of a Principal Component Analysis (PCA).

• Korean Security Journal
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• no.44
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• pp.117-137
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• 2015

As school violence gets serious, the school system created the local board against school violence in order to respond to school violence effectively. Yet, there are not many studies about the effectiveness of the local board against school violence. A few studies investigated teachers' perception about the local board while the information about the school resource officers' perception is not known much. The current study surveyed school resource officers about their perception towards the function of the local board, its member, and the response of the principal to school violence. Participants are the school resource officers working for the four metropolitan police agencies(Seoul, Kyunggi, Busan, and Ulsan) in Korea, and were asked to answer to structured and open-ended questions. The results indicated that the officers thought the local board did not very well for the function of protecting the victim's rights. In addition, they believed that the participation of parents needs to be limited in the membership, and more experts should be included in the membership of the local board. They also thought the principals should be tough in dealing with school violence. The discussion includes ideas about improving professionalism of the membership and making changes on the related regulations.

• Journal of Korean Academy of Nursing
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• v.26 no.3
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• pp.531-543
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• 1996

This study was done to develop a Maternal Identity Scale for Pregnant Women and to test the validity and reliability of the scale. A convenience sample of 161 pregnant women were asked to complete the MISP questionnaire which consisted of 45 item, this was done from December 20, 1995 to January 15, 1996. The research procedure were as follows. The first step was to identify a conceptual definition of maternal identity using Robin(1984)'s maternal identity and maternal experience during pregnancy. The second step was to operationalize the maternal identity, that is, perception of image possible of selves as mother, maternal role play by imagination, and the experiences of various emotional responses which are embedded in the mother-fetus dyad. The third step was item development which resulted in 45 items as appropriate measurement of maternal identity are except for the perception of image possible of selves as mother. The result findings were as follows : 1) Four factors for MISP (finally 40 items) were extracted through the principal component analysis and varimax rotation, and these contributed 49.3% of the variance in the total score. All 40 items in the scale loaded above .43 on one of 4 factors. 2) Each factor was named : factor 1 was named maternal role imagery and has 10 items, factor 2 was named happiness and has 11 items, factor 3 was named maternal fetal interaction and has 10 items, and the last factor 4 was named negative emotion and has 9 items. 3) Cronbach's -alpha coefficient for internal consistsncy was .92 for the total 40 items and .89, .90, .86, .78 for the four subscales in that order. Recommendations are suggested below : 1) The developed MISP be used to assess maternal readiness in pregnancy. 2) Replication study be done to test validity and relaibility. 3) For the overall measure of Maternal Identity in Pregnancy, scale for the perception of image possible of selves as mother, and cognitive domain be reorganized for the maternal identity in pregnancy. 4) It is necessary to identify variables that influences maternal pregnancy. 5) It Is necessary to identify that maternal identity in pregnancy is a reliable index of motherhood, to do correlation studies on maternal identity and major maternal variables in maternal transition period, to reoperationalize the maternal identity in postpartum, and finally to designate a longitudinal study of the maternal identity changes or stabilities.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.3
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• pp.379-384
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• 2010

The principal objective of this experiment was to determine the effects of dietary betaine on IGF-I, IGFBP-3 and IGFBP-1 secretion and IGF-I mRNA gene expression in the serum and liver of laying hens. A total of 72 ISA-Brown laying hens were fed with four different levels of betaine (0, 300, 600, 1,200 ppm) based on a corn-soybean meal diet containing 2,800 kcal/kg of metabolizable energy (ME) and 16% crude protein (CP) for four weeks. The results indicated significantly higher serum and liver IGF-I concentrations in the laying hens fed with 600 and 1,200 ppm betaine (p<0.05) compared to controls. IGF-I gene expression in liver showed a statistically correlated increase in 600 and 1,200 ppm betaine-fed groups as compared to the controls (p<0.05). Serum IGFBP-3 concentrations were elevated significantly in the groups fed 600 ppm of betaine. However, the secretion of IGFBP-1 in the liver of laying hens fed on 600 and 1,200 ppm of betaine was significantly lower than in the controls (p<0.05). The results of this experiment showed that dietary betaine supplementation plays a pivotal role in changes of the IGFs system in laying hens.

• Journal of Environmental Policy
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• v.9 no.2
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• pp.57-81
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• 2010

Recently, labor unions' active participation in social issues is drawing people's attention as their concerns are expanding from the conventional wage raise and employment to others such as the environment and poverty eradication. This derives from the notion that a trade union with bargaining power is also an economic agent responsible and able to take a positive role in social issues. This paper explains through a micro economic analysis model that labor union movements can also contribute to social issues such as the global environment. Based on the international oligopoly trade theory, the study analyzes the principal-agent model whereby firms and labor unions pursue their strategic choices based on their interest and influence the implementation of regulatory policies on pollution emission. The analysis confirmed that labor unions' bargaining power and international cooperation are influential in alleviating global pollution emission and in improving social welfare. This conclusion could be presented as a basis for arguing for and requesting the participation and cooperation of labor unions to solve environmental problems discussed at WILL 2006.