• Composites Research
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• v.22 no.3
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• pp.35-43
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• 2009

In this study, for a radiator hose made of carbon black filled EPDM(ethylene-propylene diene monomer) rubber, a measuring method of crosslink density was established to analyze the aging behaviors under thermo-oxidative stresses. At $125^{\circ}C$, the crosslink density of the rubber specimens decreased slightly in the initial stage, but increased with increasing the aging time. Such variation in crosslink density was similar to that of tensile strength. This might be due to the formation of sulphoxide crosslinks as well as to additional crosslinks made by the reaction of unvalcunized sulfurs. A high temperature aging of rubber specimens at $180^{\circ}C$ caused a slight increase in crosslink density while it did a large decrease in tensile strength and elongation. With aging at high temperature, the formation of carbonyl groups in EPDM molecule chain and formation of sulphoxide crosslink, rather than the crosslink density variation itself, had a large influence on such changes in mechanical property.

• Animal Bioscience
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• v.35 no.9
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• pp.1408-1417
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• 2022

Objective: The objective of this study was to determine whether dietary black soldier fly (Hermetia illucens, HI) larvae oil (HILO) could serve as an alternative fat source to soybean oil (SBO) in laying hen diets. Methods: We randomly assigned 25-week-old Hy-line Brown laying hens (n = 144) to receive (n = 6 hens/group; eight replicates) a control or an experimental diet in which SBO was replaced with 50% (50HILO) or 100% HILO (100HILO). Results: Dietary HILO did not negatively affect body weight or productive performance during the study. The eggs also had similar quality parameters, proximate composition, and cholesterol levels. However, the yolk color index was significantly higher (p<0.01) in the 100HILO than in the other groups. Dietary HILO significantly altered the composition of fatty acids (FAs) in abdominal fat and eggs. Total saturated fatty acids (SFAs) and total polyunsaturated FAs (PUFAs) were significantly increased and decreased in the 50HILO and 100HILO groups, respectively, compared with those in the control group (p<0.001 and p<0.0001, respectively). Specifically, the medium-chain FAs lauric and myristic acids were remarkably increased in the abdominal fat of laying hens fed HILO (p<0.0001), whereas only myristic acid increased in eggs (p<0.0001). Undesirable heavy metal (aluminum, fluorine, arsenic, lead, mercury, and cadmium) concentrations were below permissible limits in eggs. Conclusion: We considered that HILO could be an alternative dietary fat to SBO for laying hens with maintained productive performance and good egg quality.

• Korean Journal of Veterinary Service
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• v.41 no.2
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• pp.111-118
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• 2018

This study was carried out to investigate the prevalence of honeybee (Apis mellifera) diseases in Gwangju area. From November 2016 to August 2017, 89 samples were collected from 33 apiculture farms and reverse transcriptase-polymerase chain reaction (RT-PCR), polymerase chain reaction (PCR), and real time PCR were conducted. 14 infectious pathogens, including seven viruses, two bacteria, three fungi, and two parasites, were investigated from random apiculture farms in Gwangju. The percentage of infectious pathogens were as follows: Stonebrood (76.4%), Deformed wing virus (51.7%), Nosema (27.0%) in PCR and RT-PCR. This result indicated that Stonebrood was most prevalent disease in Gwangju area. And we could get similar results from real time PCR. 84.8% of farms have more than two of infectious pathogens. Stonebrood and Deformed wing virus were major diseases in almost all seasons and Black queen cell virus disease was especially prevalent in May.

• Journal of Ginseng Research
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• v.42 no.1
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• pp.116-121
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• 2018

Background: Black ginseng (BG) has greatly enhanced pharmacological activities relative to white or red ginseng. However, the effect and molecular mechanism of BG on muscle growth has not yet been examined. In this study, we investigated whether BG could regulate myoblast differentiation and myotube hypertrophy. Methods: BG-treated C2C12 myoblasts were differentiated, followed by immunoblotting for myogenic regulators, immunostaining for a muscle marker, myosin heavy chain or immunoprecipitation analysis for myogenic transcription factors. Results: BG treatment of C2C12 cells resulted in the activation of Akt, thereby enhancing hetero-dimerization of MyoD and E proteins, which in turn promoted muscle-specific gene expression and myoblast differentiation. BG-treated myoblasts formed larger multinucleated myotubes with increased diameter and thickness, accompanied by enhanced Akt/mTOR/p70S6K activation. Furthermore, the BG treatment of human rhabdomyosarcoma cells restored myogenic differentiation. Conclusion: BG enhances myoblast differentiation and myotube hypertrophy by activating Akt/mTOR/p70S6k axis. Thus, our study demonstrates that BG has promising potential to treat or prevent muscle loss related to aging or other pathological conditions, such as diabetes.

• Cross-Cultural Studies
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• v.39
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• pp.153-176
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• 2015

Poet, painter and publisher, Roland $Gigu{\grave{e}}re$ is one of Quebec's outstanding figures, inspired by both Surrealism and Quebec nationalism. He participated in contemporary artistic movement 'Phases' and influenced collective self-awareness and political ferment, 'Quiet Revolution'. In La Main au feu(1973), his poetry represent a landscape dominated by darkness in contrast with red color of fire from the volcanic crater. The world is immersed in darkness of despair which allude to the Great Darkness of Quebec society. Acts of violence assume many different forms: crows, black rain, dark flow, frenzy of knife blows. Both things and humans are in the state of absence or lack. Life falls into opacity of death. In the background of dark landscape, we discover Miror, a singular character. Similar to chain of mountains and to bare forest, he is a creature that shape the tragic inner world of poet. He is as like as seismograph that record the tremble of being. Finally, in order to fight the darkness of environment, the poet attempt to use the power of fire of volcanoes. The flow of magma become paintings of his dream and the flame of eruption, poetry of cry toward the sky. 'La main au feu' means the will to resist injustice and repression in the world. The tragic reality is replaced by a dream that become second reality out of reach of the force of hostile external circumstances.

• The Plant Pathology Journal
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• v.38 no.2
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• pp.159-166
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• 2022

Barley yellow dwarf virus (BYDV) has been a major viral pathogen causing significant losses of cereal crops including oats worldwide. It spreads naturally through aphids, and a rapid, specific, and reliable diagnostic method is imperative for disease monitoring and management. Here, we established a rapid and reliable method for isothermal reverse transcription recombinase polymerase amplification (RT-RPA) combined with a lateral flow strips (LFS) assay for the detection of BYDV-infected oat samples based on the conserved sequences of the BYDV coat protein gene. Specific primers and a probe for RT-RPA reacted and optimally incubated at 42℃ for 10 min, and the end-labeled amplification products were visualized on LFS within 10 min. The RT-RPA-LFS assay showed no cross-reactivity with other major cereal viruses, including barley mild mosaic virus, barley yellow mosaic virus, and rice black streaked dwarf virus, indicating high specificity of the assay. The sensitivity of the RT-RPA-LFS assay was similar to that of reverse transcription polymerase chain reaction, and it was successfully validated to detect BYDV in oat samples from six different regions and in individual aphids. These results confirm the outstanding potential of the RT-RPA-LFS assay for rapid detection of BYDV.

• Journal of Korean Society for Quality Management
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• v.50 no.2
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• pp.221-233
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• 2022

Purpose: This study investigates how the salespersons behave in coordinating the multiple communication channels during supplier integration (SI) for new product development (NPD), especially when their engineers directly collaborate with the buyer. Methods: This study conducted a qualitative study to explore the dynamics of the supplier's salespersons during SI for NPD. With the support of a consumer goods manufacturer (focal firm) in South Korea, we interviewed several managers, including purchasing and engineering, from the focal firm and salespersons from eight tier-1 suppliers of the focal firm. Results: The results found that the supplier's salespersons show two different behaviors toward managing and controlling the collaboration between their engineers and the buyer: (1) Process regulating behaviors that control the flows of information or communication between the engineers and the buyer, and (2) knowledge regulating behaviors that directly and indirectly support the engineers to be equipped with accurate and complete knowledge so that they can share the right knowledge with the buyer. Conclusion: This study contributes to academia and practitioners as follows. To academia, this study fill the gap in the literature by introducing the distinct behaviors of the supplier's salesperson in SI for NPD. To practitioner, in addition, our findings present coordination mechanisms to manage and control multiple communications within an inter-organizational collaboration.

• Journal of the Korean Society of Food Culture
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• v.21 no.1
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• pp.8-16
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• 2006

This study was performed by questionnaire to investigate the preference and intake frequency of Korean traditional commercial beverages. The subjects were consisted of 320 participants in Daegu and Kyungpook area. 'Chain market' scored 49.4% as purchasing place of traditional beverages. 'Tea bag' scored 31.6% as the favorite package of traditional beverages. On the reasons of drinking traditional beverage 'good for health' scored the highest with 31.3% respondents, followed by 'good smell' with 14.4%. Coffee and traditional tea were the choice of beverage after having a rich meal and on occasion of entertaining guests. The favorite foods in ordinary days were 'tea', 'alcohol', 'ice cream', 'nuts' and 'cookie'. More than thirty percent of the respondents, both male and female, raised the need of improvement in taste of traditional beverage. In the intake frequency, Korea traditional beverages obtained 1.80 points as a whole. 'Green tea' scored highest(3.40points) while 'mulberry-leaf tea' received the lowest score of 1.31 points. The preferred Korean traditional drinks were 'greed tea', 'shick hae', 'citron tea', 'misitgaru', 'maesil tea', 'rice tea' in the order. On the other hand, the preference for 'mulberry-leaf tea', 'boxthom tea', 'ginger tea', 'chrysanthemum tea' and 'omija tea' was very low. The people who are on twenties preferred 'shick hae', 'honey tea', 'citron tea', 'black tea' and 'misitgaru' more than the other generation.

• Journal of Animal Science and Technology
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• v.49 no.3
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• pp.405-414
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• 2007

Pigs have been considered as an ideal source of donor organs because of their plentiful supply and their numerous anatomical and physiological similarities to the human in xenotransplantation. However, for the public health risks associated with the potential for porcine endogenous retrovirus(PERV) infection through xenograft from pig to human, the investigation of methods for elimination and/or control of PERV has been required. In this study we developed the detection and classification methods for PERV based on PCR using specific primers. PERV-A and PERV-B were found in all pigs including Berkshire, Duroc, Landrace, Yorkshire, miniature pig, and Korean native black pig from Jeju by PCR with type-specific primers for PERV. However, PERV-C was detected only from Duroc, miniature pig, and Korean native black pig from Jeju. PERV-A and PERV-B could be distinguished by PCR-RFLP with BamHI. These methods for PERV will be useful in rapid screening of safe organ for xenograft, furthermore, helpful in monitoring of PERV during and after xenotransplantation.

• Applied Biological Chemistry
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• v.50 no.4
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• pp.276-280
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• 2007

Buckwheat often causes severe allergic reactions in sensitive people. One of the major allergenic proteins in common buckwheat (Fagopyrum esculentum) has been found to be a BW10KD protein. In this study, we developed a PCR method to detect buckwheat ingredients in food using primers corresponding to the allergenic BW10KD gene. Five pairs of oligonucleotide primers successfully enabled PCR amplification of the specific regions of the genomic BW10KD DNA from buckwheat, but no amplification from seven other cereals and beans (barley, wheat, German millet, African millet, soybean, red bean, and black bean). The proposed PCR method was applied to analyze 12 processed foods (buckwheat flour, buckwheat noodle, buckwheat jelly, wheat noodle, instant noodle, black sesame gruels, sunsik, cookie, misutkaru, and three kinds of cereal); among them, only three samples including buckwheat flour, buckwheat noodle and buckwheat jelly showed a positive reaction to the detection. This PCR method was able to detect as little as 1 ng of common buckwheat DNA. This rapid and specific PCR method would be applicable to detect allergenic buckwheat ingredients in food.