• Korean Journal of Plant Tissue Culture
• /
• v.27 no.6
• /
• pp.423-428
• /
• 2000

In 1997 when cloned sheep Dolly and soon after Polly were born, it had become head-line news because in the former the nucleus that gave rise to the lamb came from cells of six-year-old adult sheep and in the latter case a foreign gene was inserted into the donor nucleus to make the cloned sheep produce human protein, factor IX, in e milk. In the last few years, once the realm of science fiction, cloned mammals especially in livestock have become almost commonplace. What the press accounts often fail to convey, however, is that behind every success lie hundreds of failures. Many of the nuclear-transferred egg cells fail to undergo normal cell divisions. Even when an embryo does successfully implant in the womb, pregnancy often ends in miscarriage. A significant fraction of the animals that are born die shortly after birth and some of those that survived have serious developmental abnormalities. Efficiency remains at less than one % out of some hundred attempts to clone an animal. These facts show that something is fundamentally wrong and enormous hurdles must be overcome before cloning becomes practical. Cloning researchers now tent to put aside their effort to create live animals in order to probe the fundamental questions on cell biology including stem cells, the questions of whether the hereditary material in the nucleus of each cell remains intact throughout development, and how transferred nucleus is reprogrammed exactly like the zygotic nucleus. Stem cells are defined as those cells which can divide to produce a daughter cell like themselves (self-renewal) as well as a daughter cell that will give rise to specific differentiated cells (cell-differentiation). Multicellular organisms are formed from a single totipotent stem cell commonly called fertilized egg or zygote. As this cell and its progeny undergo cell divisions the potency of the stem cells in each tissue and organ become gradually restricted in the order of totipotent, pluripotent, and multipotent. The differentiation potential of multipotent stem cells in each tissue has been thought to be limited to cell lineages present in the organ from which they were derived. Recent studies, however, revealed that multipotent stem cells derived from adult tissues have much wider differentiation potential than was previously thought. These cells can differentiate into developmentally unrelated cell types, such as nerve stem cell into blood cells or muscle stem cell into brain cells. Neural stem cells isolated from the adult forebrain were recently shown to be capable of repopulating the hematopoietic system and produce blood cells in irradiated condition. In plants although the term$\boxDr$ stem cell$\boxUl$is not used, some cells in the second layer of tunica at the apical meristem of shoot, some nucellar cells surrounding the embryo sac, and initial cells of adventive buds are considered to be equivalent to the totipotent stem cells of mammals. The telomere ends of linear eukaryotic chromosomes cannot be replicated because the RNA primer at the end of a completed lagging strand cannot be replaced with DNA, causing 5' end gap. A chromosome would be shortened by the length of RNA primer with every cycle of DNA replication and cell division. Essential genes located near the ends of chromosomes would inevitably be deleted by end-shortening, thereby killing the descendants of the original cells. Telomeric DNA has an unusual sequence consisting of up to 1,000 or more tandem repeat of a simple sequence. For example, chromosome of mammal including human has the repeating telomeric sequence of TTAGGG and that of higher plant is TTTAGGG. This non-genic tandem repeat prevents the death of cell despite the continued shortening of chromosome length. In contrast with the somatic cells germ line cells have the mechanism to fill-up the 5' end gap of telomere, thus maintaining the original length of chromosome. Cem line cells exhibit active enzyme telomerase which functions to maintain the stable length of telomere. Some of the cloned animals are reported prematurely getting old. It has to be ascertained whether the multipotent stem cells in the tissues of adult mammals have the original telomeres or shortened telomeres.

• Korean Journal of Weed Science
• /
• v.32 no.3
• /
• pp.240-255
• /
• 2012

The objectives of this study were to investigate the levels of phytotoxicity of rice varieties to HPPD (4-hydroxy phenylpyruvate dioxygenase)-inhibiting herbicides known for their efficiency to control the sulfonylureas-resistant weed species：mestrione, benzobicyclone, and tefuryltrione. The twenty-six rice varieties (8-Japonica ${\times}$ Indica-type varieties and 18-Japonica-type varieties) were grown for 25 days on seedling trays and then transplanted to paddy rice fields followed by herbicide treatment i.e. standard and double doses of there respective herbicides at 5, 10, and 15 days after transplanting. Although mestrione, benzobicyclone and tefuryltrione are all HPPD-inhibiting herbicides, the phytotoxicity symptoms of the different rice varieties based on the timing of application and doses of the herbicides were significantly different. The Japonica ${\times}$ Indica-type varieties showed much more phytotoxicity symptoms than Japonica-type varieties in all applied herbicides. Increasing herbicidal doses of mesotrione, and an earlier application of and increasing herbicidal doses of benzobicyclon caused severe phytotoxicity symptoms. On the other hand, phytotoxicity due to tefuryltrione did not exhibit significant differences between rice varieties in either the timing of application or dose of the herbicide. Regardless of timing of application and dose of the herbicides, Hangangchalbyeo-1, Hyangmibyeo-1 and high-yield rice varieties such as Namcheonbyeo, Dasanbyeo, Areumbyeo, and Hanareumbyeo, which belong to the Japonica ${\times}$ Indica-type varieties, showed 5 to 8 levels of phytotoxicity symptoms including albinism, browning, detached leaf, and necrosis to mesotrione and benzobicyclon whereas only 1 to 3 levels of phytotoxicity symptoms (chlorosis, albinism, and browning) were seen with to tefuryltrione application. The Japonica-type varieties exhibited only slight phytotoxicity symptoms (1~2 levels) in conformity with the timing of application and doses of the herbicides. However, there were significant differences among the Japonica-type rice varieties, depending on the type of herbicide. Thirteen-Japonica type rice varieties were sensitive to benzobicyclone while 4-Japonica-type and 7-Japonica-type varieties showed phytotoxicity symptoms such as chlorosis and albinism with mestrione and tefuryltrione application, respectively. Therefore, we suggest that the combined-type herbicides including mestrione, benzobicyclone and tefuryltrione should be rejected in paddy fields where rice is grown for either human consumption (functional or processed rice) or livestock feed because of severe phytotoxicity symptoms on the various rice varieties seen regardless of the timing of application and doses of the herbicides.

• Journal of Intelligence and Information Systems
• /
• v.17 no.2
• /
• pp.109-117
• /
• 2011

The exhibition industry, as technology-intensive, eco-friendly industry, contributes to regional and national development and enhancement of its image as well, if it joins cultural and tourist industry. Therefore, We need to revitalize the exhibition industry, as actively holding an exhibition event. However, to attract a number of exhibition audience, the work of enhancing audience satisfaction and awareness of value for participation should be prioritized after improving quality of service within exhibition hall. As one way to enhance the quality of service, it is thought that the way providing personalized service geared toward each audience is needed. that is, if audience avoids the complexity in exhibition space and it affords them service to enable effective time and space management, it will improve the satisfaction. All such personalized service affordable lets the audience's preference on the basis of each audience profile registered in advance online grasp. and Based on this information, it is provided with exhibition-related information suited their purpose that is the booth for the interesting audience, the shortest path to go to the booth and event via audience's smart phone. and it collects audience's reaction information, such as visiting the booth, participating the event through offered the information in this way and location information for the flow of movement, the present position so that it makes revision of existing each audience profile. After correcting the information, it extracts the individual's preference. hereunder, it provides recommend booth and event information. in other words, it provides optimal information for individual by amendment based on reaction information about recommending information built on basic profile. It provides personalized service dynamic and interactive with audience. This paper will be able to provide the most suitable information for each audience through circular and interactive structure and designed smart-phone application supportable for updating dynamic and interactive personalized service that is able to afford surrounding information in real time, as locating movement position through sensing. The proposed application collects user‘s context information and carrys information gathering function collecting the reaction about searched or provided information via sensing. and it also carrys information gathering function providing needed data for user in exhibition hall. In other words, it offers information about recommend booth of position foundation for user, location-based services of recommend booth and involves service providing detailed information for inside exhibition by using service of augmented reality, the map of whole exhibition as well. and it is also provided with SNS service that is able to keep information exchange besides intimacy. To provide this service, application is consisted of several module. first of all, it includes UNS identity module for sensing, and contain sensor information gathering module handling and collecting the perceived information through this module. Sensor information gathered like this transmits the information gathering server. and there is exhibition information interfacing with user and this module transmits to interesting information collection module through user's reaction besides interface. Interesting information collection module transmits collected information and If valid information out of the information gathering server that brings together sensing information and interesting information is sent to recommend server, the recommend server makes recommend information through inference with gathered valid information. If this server transmit by exhibition information process, exhibition information process module is provided with user by interface. Through this system it raises the dynamic, intelligent personalized service for user.

• Journal of Intelligence and Information Systems
• /
• v.17 no.2
• /
• pp.77-96
• /
• 2011

An exhibition is defined as market events for specific duration to present exhibitors' main products to business or private visitors, and it plays a key role as effective marketing channels. As the importance of exhibition is getting more and more, domestic exhibition industry has achieved such a great quantitative growth. But, In contrast to the quantitative growth of domestic exhibition industry, the qualitative growth of Exhibition has not achieved competent growth. In order to improve the quality of exhibition, we need to understand the preference or behavior characteristics of visitors and to increase the level of visitors' attention and satisfaction through the understanding of visitors. So, in this paper, we used the observation survey method which is a kind of field research to understand visitors and collect the real data for the analysis of behavior pattern. And this research proposed the following methodology framework consisting of three steps. First step is to select a suitable exhibition to apply for our method. Second step is to implement the observation survey method. And we collect the real data for further analysis. In this paper, we conducted the observation survey method to obtain the real data of the KIDS & EDU EXPO for Children in SETEC. Our methodology was conducted on 160 visitors and 78 booths from November 4th to 6th in 2010. And, the last step is to analyze the record data through observation. In this step, we analyze the feature of exhibition using Demographic Characteristics collected by observation survey method at first. And then we analyze the individual booth features by the records of visited booth. Through the analysis of individual booth features, we can figure out what kind of events attract the attention of visitors and what kind of marketing activities affect the behavior pattern of visitors. But, since previous research considered only individual features influenced by exhibition, the research about the correlation among features is not performed much. So, in this research, additional analysis is carried out to supplement the existing research with data mining techniques. And we analyze the relation among booths using data mining techniques to know behavior patterns of visitors. Among data mining techniques, we make use of two data mining techniques, such as clustering analysis and ARM(Association Rule Mining) analysis. In clustering analysis, we use K-means algorithm to figure out the correlation among booths. Through data mining techniques, we figure out that there are two important features to affect visitors' behavior patterns in exhibition. One is the geographical features of booths. The other is the exhibit contents of booths. Those features are considered when the organizer of exhibition plans next exhibition. Therefore, the results of our analysis are expected to provide guideline to understanding visitors and some valuable insights for the exhibition from the earlier phases of exhibition planning. Also, this research would be a good way to increase the quality of visitor satisfaction. Visitors' movement paths, booth location, and distances between each booth are considered to plan next exhibition in advance. This research was conducted at the KIDS & EDU EXPO for Children in SETEC(Seoul Trade Exhibition & Convention), but it has some constraints to be applied directly to other exhibitions. Also, the results were derived from a limited number of data samples. In order to obtain more accurate and reliable results, it is necessary to conduct more experiments based on larger data samples and exhibitions on a variety of genres.

• Journal of Distribution Research
• /
• v.16 no.1
• /
• pp.65-93
• /
• 2011

This paper aims to explore how relational constructs(supplier's idiosyncratic investment, retailer's dependence, and dyadic communication) impact the buyer's trust across the relationship lifecycle. Companies make great efforts to create trust and maintain long-term relationship with buyers. Buyer and supplier relationships evolve through distinct lifecycles. In each phase, buyers and suppliers exhibit different patterns of behaviour. Also, they have different attitudes toward, and expectation of, one another. In this study, the final outcome investigated is long-term orientation from the buyer's perspective. Data were collected from 296 survey questionnaires of retailers engaging in Crops Protected Material industry in Korea. Exploratory factor analysis and confirmatory factor analysis were used to purify the measurement scales. And structural equation analysis and Chow test were used to test the hypotheses. The result indicates that the effect of retailer's dependence on the trust is greatest. Especially, the effect of dependence is growing as the relationship has developed. Supplier's idiosyncratic investment increases trust in the early phase, while it is not found to affect trust in the maturity phase. In the early phase, the determination of trust begins to be increasingly influenced by partner's relationship investment only because other clues are not observed yet. Reciprocal communication has a positive effect on trust, and long-term orientation is directly influenced by retailer's trust. Communication's effect is greater in the build-up phase than in the maturity phase. A limitation of this study is the unequal sample size in each of the relationship phases. Literature has suggested that the effects of relational constructs on outcomes are different across relationship phases. This study shows that different relational constructs have different effects on trust depending upon the relationship phase.

• Journal of The Korean Association of Information Education
• /
• v.12 no.1
• /
• pp.9-22
• /
• 2008

The purpose of this research is to develop a prototype of the support system in order for team building associated with web-based project learning having applied Kolb's learning style. To accomplish this purpose, the following research tasks were performed. First, core idea in order to embody the system's value, key activities, tools that will support pertinent activities and the strategy so as to develop guidelines, etc. were devised and prepared. Second, a system was designed on the basis of structural model of teaching design, then after, interface was developed. The core factors in this system are inspection of learning style, organizing a team and team building. Above all, it is required to make learners know about learning environments, of which they are in favor, and also its distinctive features through inspection of learning style, and then focusing on learning style, a team should be organized insomuch as to accommodate a variety of learning styles as much as possible. For the purpose of team building, after learning style of each constituent member of the team has been made known, then the roles will be divided among the constituent members of the team so as to suit their individual characteristics referring to each of their learning styles that have been exposed. To verify the value of this system developed and efficiency thereof, a focus group interview was conducted. The focus group consisted of professionals, all from related fields. After the interview, the points required to make further improvements were elicited and taken care of by follow-up actions as needed. And having reflected such improvements made, the final system was developed. With this newly developed system, learners can get the results of inspection of learning style so quickly by performing inspection any time any where, and based on the results from such inspection, a team comprising dissimilar constituents who exhibit a variety of different propensities will be automatically organized. Thus, this system may be used not only for web-based project learning having unspecified persons elected as constituents, but in the offline space also.

• Journal of the Korean Institute of Traditional Landscape Architecture
• /
• v.28 no.1
• /
• pp.27-37
• /
• 2010

This study tries to illuminate the features and values of the Buddhist temple Palkyung by closely examining the forms, structures, and meanings of Tongdo-palkyung(通度八景) handed down at Tongdosa Temple, the best among Korea's Buddhist temples with its three treasures of Buddha, law of Buddha and Buddhist monks. The findings of this study can be summarized as the following. First of all, it reveals the meaning of the geographical name Yeongchuksan(靈鷲山), located to the west of Tongdosa, and a spectacular sight spread like an eagle's spread wings, as well as its location and spatial features. In particular, the arrangement features of a number of attached hermitages clearly show Yeongchuksan's world as being a temple with buddhist treasures. The multi-layered unfolding and centripetal intention of the scenery can be perceived through the shape of the Sshangryongnongju(雙龍弄珠形), around Tongdosa and the feature of the enclosed landscape encircling the steps of Hyeolcheo(穴處) Geumganggyedan. The substances and components of Tongdopalkyung include sound-based spectacles derived from Beoneumgu(梵音具) creating sounds related to religious rituals to enlighten and redeem mankind, such as Yeongji(影池: a holy pond with shadow reflections), drum sounds, and bell sounds along with physical features like pine trees, Dae(臺), waterfalls, Dongcheon (洞天), and a glow in the sky. On the other hand, Palkyung's geographical arrangements exhibit a circular spatial formation based on the main motif as Buddhist symbolism, beginning with the 'Gukjangsangseokpyo(國長生石標)' awakening the territoriality of Tongdosa and locating the first scene 'Mupunghansong(舞風寒松)' in its introductory area, with the features of water, bridge, pine grove, and Iljumun(gate) to stand for the influx. Six other scenes including 'Anyangdongdae(安養東臺)' are placed in the sacred precincts around Daeungjeon and Geumganggyedan while the glow of sunset at 'Danjoseong' just outside the domain closes the symbolic circular formation of the Tongdopalkyung, which coincides with the development of the Mandala figure symbolizing 'Gusanpalhae(九山八海)' centered in Sumisan(須彌山). What is more, Tongdopalkyung, while excluding primary scenic elements inside the temple, maximizes the domain of the mountain's entrance and the effects of the multi-layered mountain, mountain upon mountain, by intensifying the influx and centripetal qualities. The Tongdopalkyung analysis reveals the antithesis of four-coupled scenes conveying buddhist principles and thoughts on the basis of seasons, directions, space and time to display a narrative structural landscape when viewed from the temple's territoriality. Likewise, the characteristics and porch structures of Tongdopalkyung are tools and language of symbols to both externally strengthen the temple's territoriality and to internally, maximize the desires to the Land of Happiness as well as intensify religious wishes and the Mandala's multi-layered qualities through the meanings of time and space.

• Resources Recycling
• /
• v.17 no.4
• /
• pp.21-29
• /
• 2008

Waste shell powder was added to the high density polyethylene(HDPE), and resultant mechanical properties and flame retardancy were analyzed in terms of shell content. Compatibilizer(PE-g-MA) was used to enhance the mechanical properties of the prepared HDPE/shell composites, and several flame retardant agents($Al_2O_3$, $Sb_2O_3$) were utilized to improve flame retardancy. Addition of the compatibilizer resulted in an improved mechanical properties due to the increased interfacial bonding between HDPE matrix and shell powder. In the case of impact strength, it even reached to the impact strength of pure HDPE. Also the addition of the flame retardant agents did not exhibit mechanical property decrease. UL-94 flammability test on the prepared HDPE/shell composites indicated that at 40wt% of shell only inclusion, time to ignite the flame and the total time of flame duration increased. When flame retardant agents mixed with shell powder were added to the HDPE matrix, improved flame retardancy was observed. Generally, flame retardancy effect of $Al_2O_3$ was better than $Sb_2O_3$. UL-94 V-0 classification was observed for the specimens with $Al_2O_3$ and compatibilizer at more than 40wt% shell, and also for specimens with $Sb_2O_3$ and compatibilizer at all shell content.

• Clinical and Experimental Pediatrics
• /
• v.53 no.4
• /
• pp.481-487
• /
• 2010

Purpose: Recently many studies show early exposure during childhood growth to endotoxin (lipopolysaccharides, LPS) and/or early exposure to allergens exhibit important role in development of allergy including bronchial asthma. The aim of this study was to evaluate the role of endotoxin and allergen exposure in early life via the airways in the pathogenesis of allergic airways inflammation and airway hyperresposiveness (AHR) in mouse model of asthma. Methods: Less than one week-old Balb/c mice was used. Groups of mice were received either a single intranasal instillation of sterile physiologic saline, 1% ovalbumin (OVA), LPS or $1.0{\mu}g$ LPS in 1% OVA. On 35th day, these animals were sensitized with 1% OVA for 10 consecutive days via the airways. Animals were challenged with ovalbumin for 3 days on 55th days, and airway inflammation, hyperresponsiveness, and cytokine expression were assessed. Measurements of airway function were obtained in unrestrained animals, using whole-body plethysmography. Airway responsiveness was expressed in terms of % enhanced pause (Penh) increase from baseline to aerosolized methacholine. Lung eosinophilia, serum OVA-IgE and bronchoalveolar lavage (BAL) fluid cytokine levels were also assessed. ANOVA was used to determine the levels of difference between all groups. Comparisons for all pairs were performed by Tukey-Kramer honest significant difference test; $P$ values for significance were set to 0.05. Results: Sensitized and challenged mice with OVA showed significant airway eosinophilia and heightened responsiveness to methacholine. Early life exposure of OVA and/or LPS via the airway prevented both development of AHR as well as bronchoalveolar lavage fluid eosinophilia. Exposure with OVA or LPS also resulted in suppression of interleukin (IL)-4, 5 production in BAL fluid and OVA specific IgE in blood. Conclusion: These results indicate that antigen and/or LPS exposure in the early life results in inhibition of allergic responses to OVA in this mouse model of astham. Our data show that early life exposure with OVA and/or LPS may have a protective role in the development of allergic airway inflammation and development of allergen-induced airway responses in mouse model of asthma.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.36 no.5
• /
• pp.515-520
• /
• 2007

This study was peformed to determine the antioxidative, antimutagenic and cytotoxic effects of the natural seasoning using Lentinus edodes powder (NSLP) by DPPH (2,2-diphenyl-1-picrylhydrazyl) free radical donating method, Ames test, and cytotoxicity, respectively. The scavenging effect on DPPH radical in ethyl acetate fraction of NSLP showed $155{\mu}g\;of\;RC_{50}$. The direct antimutagenic effects of ethanol extract and its solvent fractions of NSLP were examined by Ames test using Salmonella Typhimurium TA98 and TA100. In the Ames test, ethanol extract of NSLP alone did not exhibit any mutagenicity and most of the samples showed high antimutagenic effects against mutation induced by N-methyl-N'-nitro-N-nitroso guanidine (MNNG) and 4-nitroquinoline-1-oxide (4NQO). Ethyl acetate fraction of NSLP ($200{\mu}g/plate$) showed approximately 82% inhibitory effect on the mutagenesis induced by 4NQO against TA98 strain, whereas 84% and 80% inhibitions were observed on the mutagenesis induced by 4NQO and MNNG against TA100 strain. In anticancer effects of ethanol extract and its solvent fractions of NSLP against cancer cell lines including human lung carcinoma (A549), human breast adenocarcinoma (MCF-7), human hepatocellular carcinoma (Hep3B), human cervical adenocarcinoma (HeLa) and human gastric carcinoma (AGS) were investigated. The treatment of 1 mg/mL ethyl acetate fraction of NSLP showed strong cytotoxicity of 56.7%, 84.9%, 64.6%, 85.1% and 71.5% against A549, MCF-7, Hep3B, HeLa and AGS, respectively. In contrast 1 mg/mL treatment of NSLP extract and its solvent fractions had only $4{\sim}40%$ cytotoxicity on human transfomed primary embryonal kidney cell (293). From this result, it is suggested that NSLP is believed to have possible antioxidative, antimutagenic and anticancer capacities.