• Korean Journal of Poultry Science
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• v.40 no.4
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• pp.299-304
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• 2013

Tracheal epithelial cells (TECs) are an important tool for studies of viral respiratory diseases. Primary TECs have been cultured from human, mouse and hamster. It is also necessary to diagnose viral respiratory disease and reveal infection mechanisms in chicken. In this study, we isolated tracheal epithelial layers from tracheal of 20-day-old chicks and cultured primary TECs from the isolated layers. Ciliated cells which were a typical morphology of TECs were observed in cultured primary TECs and maintained until cell passage 5 (15 to 20 days). When we analyzed expression patterns of epithelial marker genes (retinoic acid responder, FGF-binding protein, virus activating protease (VAP) in TECs compared to immortalized chicken embryonic fibroblast cell line (DF-1), all the marker genes are highly expressed in TECs than in DF-1. When TECs were cultured with 0.1 and 1 MOI of ND virus (rNDV-GFP strain) to test the susceptibility of TECs for ND virus, 12.6% and 48.2% of the incubated TECs were infected respectively. In addition, when DF-1 was incubated with 1 MOI of ND virus, the virus infection rate of DF-1 was three times lower than the virus infection rate of TECs. These data could contribute to study infection mechanisms of viral respiratory diseases and control them in chicken.

• Clinical and Experimental Pediatrics
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• v.45 no.6
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• pp.754-763
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• 2002

Purpose : The incidence of type 2 diabetes in children and adolescents has been reported to increase recently. The aim of this study is to investigate the clinical features of type 2 diabetes developing during childhood and adolescent period. Methods : The medical records of 33 patients with type 2 diabetes were reviewed. We analysed clinical manifestations, demographic data, and modes and responses of treatment. Results : Age at diagnosis was $13.4{\pm}1.8$ years. Seventy percent of patients revealed pubertal signs at diagnosis. Half of the patients had BMI more than $25kg/m^2$. Seventy-three percent of patients had family history of type 2 diabetes. Acanthosis nigricans were found in 18% of patients. Nineteen(57.6%) patients were diagnosed incidentally by random urine or blood glucose test without any typical diabetic symptom or sign. The modes of therapy to control hyperglycemia were insulin alone(75.8%), oral hypoglycemic agents alone(9.1%), insulin and oral hypoglycemia agents(9.1%), and only diet with exercise(6%). At the time of investigation, 45.5% of patients were not using insulin. The typical diabetic symptoms at diagnosis were more prevalent in patients who required insulin for more than two years than patients who did not(P<0.05). Conclusion : The development of type 2 diabetes in children and adolescents is possibly related to puberty, obesity, family history, and defects in insulin secretion rather than insulin resistance. Many children and adolescents with type 2 diabetes required insulin initially and some of them could discontinue. More than half of the patients were diagnosed as diabetes without any typical symptom or sign, which might be one of the predictive factors of the prolonged insulin requirement.

• Clinical and Experimental Pediatrics
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• v.49 no.1
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• pp.71-75
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• 2006

Purpose : Because migraine in children has different characteristics from that in adults, it is inappropriate to apply migraine criteria for adults to children. Recently, the International Headache Society(IHS) revised criteria regarding children's characteristics. Therefore, we reviewed the characteristics of childhood migraines without auras based on the revised criteria and compared the data with the findings of childhood migraine by the previous criteria. Methods : Among 102 children who visited the outpatient clinic of Kangbuk Samsung Hospital for the chief complaint of headache, we analyzed the clinical findings of 34 patients, who were diagnosed as migraine without aura, and probable migraine based on the revised criteria. Results : Migraines without aura were diagnosed in 27 patients(26.5 percent) and probable migraines were observed in seven patients(6.8 percent). The usual duration of headache attacks over 2 hours was observed in 12 patients(44.4 percent). On the contrary, 15 patients(55.6 percent) usually experienced headaches for one to two hours. According to the location of headaches, there were temporal areas in 14 cases, frontal areas in nine cases, occipital areas in two cases and diffuse areas in two cases. The striking point in probable migraines is that the length of headache was below one hour in five patients. Nine patients were diagnosed as migraine without aura, when the first edition criteria was applied to same patients. Conclusion : We found that the prevalence of migraine without aura increased by the revision of IHS criteria. We hope that migraines in children will be diagnosed correctly by the new IHS criteria.

• Journal of KIISE:Computer Systems and Theory
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• v.33 no.4
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• pp.242-255
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• 2006

In the recent years, Popularization of mobile devices such as Smart Phones, PDAs and MP3 Players causes rapid increasing necessity of Power management technology because it is most essential factor of mobile devices. On the other hand, despite low price, hard disk has large capacity and high speed. Even it can be made small enough today, too. So it appropriates mobile devices. but it consumes too much power to embed In mobile devices. Due to these motivations, in this paper we had suggested methods of minimizing Power consumption while playing multimedia data in the disk media for real-time and we evaluated what we had suggested. Strict limitation of power consumption of mobile devices has a big impact on designing both hardware and software. One difference between real-time multimedia streaming data and legacy text based data is requirement about continuity of data supply. This fact is why disk drive must persist in active state for the entire playback duration, from power management point of view; it nay be a great burden. A legacy power management function of mobile disk drive affects quality of multimedia playback negatively because of excessive I/O requests when the disk is in standby state. Therefore, in this paper, we analyze power consumption profile of disk drive in detail, and we develop the algorithm which can play multimedia data effectively using less power. This algorithm calculates number of data block to be read and time duration of active/standby state. From this, the algorithm suggested in this paper does optimal scheduling that is ensuring continual playback of data blocks stored in mobile disk drive. And we implement our algorithms in publicly available MPEG player software. This MPEG player software saves up to 60% of power consumption as compared with full-time active stated disk drive, and 38% of power consumption by comparison with disk drive controlled by native power management method.

• Korean Journal of Materials Research
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• v.8 no.7
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• pp.621-627
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• 1998

The formation of Co-silicide between Co/Zr bilayer on the amorphous and crystalline Si substrates has been investigated. The films of Zr(50$\AA$) and Co(l50$\AA$) were deposited with e-beam evaporation system and were heattreated with the rapid thermal annealing system at the temperatures between 50$0^{\circ}C$ and 80$0^{\circ}C$ with 10$0^{\circ}C$ increments for 30 seconds. The phase identification of Co-silicide was carried out by XRD and the chemical analysis was examined by AES and RBS. The interface morphologies of Co/Zr bilayer films were investigated by cross sectional TEM and HRTEM. $CoSi_2$ was formed epitaxially on the crystalline Si substrate above $700^{\circ}C$ while polycrystalline $CoSi_2$ was grown on the amorphous Si substrate. The formation temperature of Co-silicide on the amorphous Si substrate was about 100 C lower than that on the crystalline Si. The COzSi phase was not identified on the both Si substrates. The formation temperature of first phase of Co-silicide on ColZr bilayer was higher than that on Co mono layer. CoSizlayer formed on the amorphous Si substrate exhibits better uniformity compared to the CoSiz formed on the crystalline substrate. The sheet resistance of CoSiz layer on crystalline Si was lower than that on the amorphous Si at high temperatures.tures.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.9 no.1
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• pp.98-104
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• 1998

A 12-year-old girl with a 6 year history of childhood-onset schizophrenia required 2 hospitalizations and long-term clozapine trial due to inadequate responses to combinations of typical neuroleptics and traditional treatments of schizophrenic disorder. On admission, she had continuous auditory and visual hallucinations, persecutory delusion, emotional instability, regression of behaviors including temper tantrums as well as specific developmental delays in learning, language, and motor coordination. The clozapine trial significantly reduced most of the positive symptoms, and facilitated in successful discharge from the hospital. During the 4 year clozapine treatment, no significant adverse reactions were noted, and she returned to a structured school setting with minimal degrees of schizophrenic symptoms. From this clinical experience, we suggest that clozapine might be safe and effective in treating treatment-refractory schizophrenic children.

• The korean journal of orthodontics
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• v.24 no.4 s.47
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• pp.917-932
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• 1994

This study was conducted to examine the changes in the shape of the Sprague-Dawley rats' articular disk following postural hyperpropulsion by observing their articular specimens through light and electronic microscopes after following 2-week and 4-week postural hyperpropulsion from their four weeks of age. The findings of this study are summarized as follows. It was shown that as compared with the control group, the experimental group indicated a significant increase in thickness of the 2-week groups' anterior and postreior portion of the articular disc. The experimental group showed statistically more significant increase in thickness of the 4-week groups' anterior portion of the articular disc than the control group. Light micrograph showed that the experimental group had more fibroblast in the anterior portion of the 2-week and 4-week groups than the comparing group. The 2-week groups showed in the findings through the electronic microscope that there were found the well developed and dilated RER which seems to actively synthesize the extracellular matrix including collagen, the cells with the well developed RER without distention which seems to actively synthesize the intracellular microfilaments due to the well developed free ribosome, and the typical chondroid cells. In addition, there was more fibroblast cell with the distended and well developed RER in the anterior area of the experimental group than that of the control group. The 4 week experimental group's anterior area of the disk had more cells than that of the control group while fibroblast with the well developed RER and free ribosome was quite abundat. Based on the above result of this study, it was shown that the functional hyperpropulsion of the mandible causes the changes in the nature of the mechanical load to the certain portion of the articular disk. As a result, it seems that there may be occurred some changes in morphology of the disc by adaptation or confrontation with these changes at the cellular level.

• Korean journal of applied entomology
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• v.47 no.1
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• pp.87-93
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• 2008

Bacillus thuringiensis with selected high toxicities against tobacco cutworm, Spodoptera litura were isolated from domestic soils. When being observed under a phase-contrast microscope, the insecticidal crystal proteins were showed a bipyramidal crystal types. New CAB 109 isolate was identified to B. thuringiensis subsp. aizawai in the H serotype. As a results of insecticidal activities between CAB 109 isolate and 3 existing ready-made products against 3rd larva of S. litura, CAB 109 isolate showed 100% mortality with spore concentration $(1.3{\times}10^7cfu/ml)$. It was a very high insecticidal activity compared with a existing ready-made B. t. products. $LD_{50}$ values of CAB 109 isolate was $9.78{\times}10^5,\;6.87{\times}10^6\;and\;1.83{\times}10^7cfu/ml$ spore concentration against 2nd, 3rd and 4th larva of S. litura, respectively. Unlike Plutella xylostella, S. litura was slowly died after application up to 7 days. The weight of S. litura larva applied with CAB 109 isolate were 6-7 times less than controlled group. Even though it didn't die, it did not grow into next larva. The result observed with scanning electron microscope was that CAB 109 isolate of B. t. aizawai formed a typical bipyramidal crystal protein type. Otherwise, when CAB 109 isolate was examined with SDS-PAGE and with trypsin, there was no difference between CAB 109 strain and ready-made products of B. thuringiensis.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.15 no.2
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• pp.153-169
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• 2020

A new way of shopping based on virtual assistant, so called voice shopping, is drawing attention. The voice shopping market is growing around the world, and Korea is on the verge of full-scale commercialization of this new shopping. For the development of voice shopping-related industries, it is necessary to research on specific issues related to this new shopping methods, such as the quality of services, efficient processes tailored to new ways, and ways to build customer relationships. As part of such an attempt, the study seeks to determine the factors that affect consumers' perception and attitudes toward voice shopping. The study conducted the analysis based on survey response data of 171 online shopping users. In addition to the typical factors of the technology acceptability model(TAM) such as perceived usefulness and ease of use, the impact of perceived playfulness was included for analyzing the intention on the acceptance of voice shopping. In particular, this study focuses on the impact of user attributes. For the spread of voice shopping, it is necessary to set up a valid target customer and understand users for establishing an effective customer relationship. Therefore, this study tries to analyze how the perceptions on the voice shopping(perceived usefulness, ease of use, and perceived playfulness) are affected by users' attributes, such as user innovativeness and user knowledge level. The result of analysis shows that user innovativeness have a positive relationship with all of perceived usefulness, ease of use, and perceived playfulness. The user knowledge base, however, was not significant to all these three variables. The user knowledge base is shown to have a positive effect on user innovativeness which is the source of positively significant factor for the variable of the perceptions on the voice shopping. Meanwhile, among the variables of extended technology acceptance model, perceived usefulness and perceived playfulness have positive effects on the acceptance of voice shopping, while ease of use has no significant impact on the voice shopping acceptance. Ease of use has a positive relationship with perceived usefulness and playfulness. This study is meaningful in providing implications on the development of voice shopping platforms and related services, and establishment of customer relationship.

• The Korean Journal of Food And Nutrition
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• v.16 no.3
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• pp.197-202
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• 2003

The purpose of this study was to investigate basic factors of obesity, nutrient intakes, behaviors of dietary life, daily energy expenditure and emphasize on the necessity of school education. Because the growing prevalence of obesity have required a need for health education in school. The results were as follows. 1. The average height of boys and girls was l59${\pm}$13cm(boys), l54${\pm}$11cm(girls). The average weight of them was 68${\pm}$16kg(boys), 70${\pm}$13kg(girls). BMI(body mass index) of them was 26.9${\pm}$3.4(boys), 29.5${\pm}$2.9(girls). 2. For energy and protein, the average intakes of subjects were higher than recommended dietary allowances for Koreans(7th Ed). The average intakes of vitamin A and ascorbic acid were much lower than the recommended dietary allowances. 3. Most of subjects prefer fast food, rich snacks and overeating, irregular meal amount and these dietary behaviors were severe problems. 4. Total energy expenditure was 1,933kcal in boys and 1,789kcal in girls. To reduce weight and treat obesity, the required energy intake to subjects was 1,546kcal(boys) and 1,431kcal(girls). If we prepared the effective program for obesity, school education should be integrated within the larger community. Parents of students and students may be educated to make good health changes in the home. Nutrition education has a direct impact on their life style of their food intake and nutritional status. The use of multi-component obesity treatments will be effective in a school setting. It is more effective to encourage health habits in school, house and it should be integrated within the larger community.