• Mycobiology
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• v.41 no.4
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• pp.234-242
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• 2013

A total of 62 bacterial isolates were obtained from Gomsohang mud flat, Mohang mud flat, and Jeju Island, Republic of Korea. Among them, the isolate CNU114001 showed significant antagonistic activity against pathogenic fungi by dual culture method. The isolate CNU114001 was identified as Bacillus amyloliquefaciens by morphological observation and molecular data analysis, including 16SrDNA and gyraseA (gyrA) gene sequences. Antifungal substances of the isolate were extracted and purified by silica gel column chromatography, thin layer chromatography, and high performance liquid chromatography. The heat and UV ray stable compound was identified as iturin, a lipopeptide (LP). The isolate CNU114001 showed broad spectrum activity against 12 phytopathogenic fungi by dual culture method. The semi purified compound significantly inhibits the mycelial growth of pathogenic fungi (Alternaria panax, Botrytis cinera, Colletotrichum orbiculare, Penicillium digitatum, Pyricularia grisea and Sclerotinia sclerotiorum) at 200 ppm concentration. Spore germ tube elongation of Botrytis cinerea was inhibited by culture filtrate of the isolate. Crude antifungal substance showed antagonistic activity against cucumber scleotiorum rot in laboratory, and showed antagonistic activity against tomato gray mold, cucumber, and pumpkin powdery mildew in greenhouse condition.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.32 no.4
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• pp.231-263
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• 2021

The purpose of this study is to analyze the information behavior of so-called "MZ Generation" users who are going to be the main information users of the continuously and radically changing scientific information environment due to the advent of various types of information media and rapid increment of digital information resources. Especially, the characteristics of MZ generation is investigated through questionnaire asking questions about their use of contents platforms, and online resources for everyday life information and scholarly information, and their way of producing, responding, and sharing information contents. The results show that they use YouTube most as the contents platform, prefer Naver as their everyday life information source, and use Google as the main scholarly information source. Their main purpose of using the content platform is to search for everyday life information rather than scholarly or professional information, and they are actively producing information, mostly to keep records of their everyday lives.

• The Journal of the Convergence on Culture Technology
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• v.8 no.4
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• pp.277-287
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• 2022

Recent trends in sharing online video contents show that vlogging on everyday life can cause meaningful changes in viewers' perception of mediated characters and their own lifestyles. We explored that flourishing everyday life video contents online are intertwined with viewers' psychological engagement such as empathy and social presence, let alone self-enhancing motivations such as self-reflection and psychological empowerment. Survey analysis results suggest that between contents types of vlog (everyday life vs. in-depth information), watching in-depth information videos significantly affected viewers' psychological engagement and self-enhancing motivations. Compared to celebrity's online videos, daily videos starring laypeople showed significantly positive impacts on viewers' engagement such as empathy, social presence, and self-enhancement such as self-reflection, psychological empowerment.

• Journal of the Korean Wood Science and Technology
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• v.51 no.4
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• pp.309-319
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• 2023

Bamboo culm is in the form of a tube/pipe, composed of internodes which are bounded by a partition/diaphragm (node). Anatomically, bamboo is composed of vascular bundles and parenchyma ground tissue. One of the constituents of vascular bundles is fibers that are grouped to form a fiber sheath. The anatomical structure of the nodes and internodes is thought to influence the strength of bamboo strips, including tensile strength. This study aimed to determine the characteristics of vascular bundles (distribution and fiber percentage) and their effects on the density and tensile strength of Gigantochloa apus bamboo strips with and without nodes. The bamboo culms were divided into three parts (outer, middle, and inner) along the radial direction. The results showed that the distribution of vascular bundles and percentage of fiber sheaths decreased significantly from the outer to the inner layer. This also had a significantly decreased density and tensile strength. Furthermore, the number of vascular bundles (in the transverse plane) was greater in the internodes than in the nodes. Anatomically, the orientation of the vascular bundles at irregular nodes is observed in the radial and tangential planes, where the direction is not only in the axial direction, but also in the radial and tangential directions. This caused the tensile strength of the G. apus bamboo strips to be lower at the nodes than at the internodes.

• Structural Engineering and Mechanics
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• v.60 no.3
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• pp.387-404
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• 2016

In this paper, the response and failure of sharp-notched 6061-T6 aluminum alloy circular tubes with five different notch depths of 0.4, 0.8, 1.2, 1.6 and 2.0 mm subjected to cyclic bending were experimentally and theoretically investigated. The experimental moment-curvature relationship exhibits an almost steady loop from the beginning of the first cycle. And, the notch depth has almost no influence on its relationship. However, the ovalization-curvature relationship exhibits a symmetrical, increasing, and ratcheting behavior as the number of cycles increases. In addition, a higher notch depth of a tube leads to a more severe unsymmetrical trend of the ovalization-curvature relationship. Focusing on the aforementioned relationships, the finite element software ANSYS was used to continue the related theoretical simulation. Furthermore, the five groups of tubes tested have different notch depths, from which five unparallel straight lines can be observed from the relationship between the controlled curvature and the number of cycles required to produce failure in the log-log scale. Finally, a failure model was proposed to simulate the aforementioned relationship. Through comparison with the experimental data, the proposed model can properly simulate the experimental data.

• Journal of Life Science
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• v.14 no.6 s.67
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• pp.1018-1022
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• 2004

Optimized conditions for Agrobacterium-mediated lisianthus pollen transformation were adjusted using various factors such as temperature, pH and sucrose concentration. Pollen tube growth was successfully achieved in a medium (pollen germination medium; PGM) containing $7-15\%$ sucrose with pH in the range of 5.5-7.0 at temperature of $20-27^{\circ}C$. Lisianthus pollen was vacuum-infiltrated with Agrobacterium cell suspension for 20 min, and transformed pollen was confirmed by GUS histochemistry and Southern hybridization following RT-PCR. Transgenic pollen system may be utilized for establishing an area of plant transient expression systems based on the convenient pollen transformation procedure presented in here.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.28 no.7
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• pp.915-922
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• 2004

A stent is small tube-like structure expanded into stenotic arteries to restore blood flow. The stent expansion behaviors define the effectiveness of the surgical operation. In this paper, finite-element method was employed to analyze expansion behaviors and fatigue life of a typical diamond-shaped balloon-expandable stent. Beyond safety considerations, this type of analysis provides mechanical properties that are often difficult to obtain by experiments. Mechanical properties of the stent expansion pressure, radial recoil, longitudinal recoil and foreshortening were simulated using commercial FEM code, ANSYS and fatigue life were estimated using NISAII ENDURE. The FEM results showed that the pressures necessary to expand the stent up to a diameter of 3mm, 4mm and 5mm were 0.75MPa, 0.82MPa and 0.97MPa. The fatigue lifes according to expansion diameter were 114${\times}$10$^{7}$cycles, 714${\times}$$^{6}$cycles and 163${\times}$10$^{6}$cycles. As a result, a finite element model used in this study can simulate expansion behaviors of stents and should be useful to design new stents or analyze actual stents.

• Journal of Life Science
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• v.6 no.4
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• pp.264-269
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• 1996

Monoclonal antibodies against the zoospores of Allomyces macrogynus were prepared using standard hybridoma technique. Mice were immunized either with the fixed zoospores or the zoospore proteins, and the production of the antibodies from the resulting hybridomas were screened by enzyme-linked immunosorbent assay (ELISA). Thirty hybridomas were initially identified ans six hybridomas were purified to the single cell clones. Culture supernatants from the hybridomas were tested for the effects on the growth of the germ tubes, and some of the hybridoma culture supernatants studied showed growth stimulatory effects.

• Journal of Life Science
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• v.14 no.4
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• pp.537-540
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• 2004

A caecostomy technique (surgery for inserting tube into caeca) was developed to quantify urine backflow into the caeca. Two days post-surgery, caecostomised chickens were flushed with 20 ml of warm saline solution every other day for 10 days. After surgery birds temporarily lost appetite and activity, but they were restored gradually in a few days. The incision healed within 10 days post-surgery. Excreta were collected daily from caecal tubing and cloaca by surgical attachment of polyethylene collection vessels to the chickens. Post-mortem examinations ascertained that the caeca were intact around the Latex tubing.

• Journal of Medicine and Life Science
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• v.17 no.1
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• pp.16-20
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• 2020

Spontaneous hemopneumothorax is a rare disease, and it can cause life threatening condition. It is characterized by the accumulation of more than 400 mL of blood and air in the pleural cavity without any other apparent causes. A previously healthy 22-year-old female patient presented with acute chest pain and dyspnea. Chest X-ray and computed tomography revealed a massive hemopneumothorax in the left hemithorax. The images showed a completely collapsed left lung with right-sided tracheal deviation, several pleural adhesion bands, and fluid collection with air-fluid level. We emergently performed a closed thoracostomy, and then 560 mL of fresh bloods were initially drained. We considered an emergent video-assisted thoracoscopic surgery for pulmonary wedge resection and bleeding control because of the massive hemothorax. However, the patient's vital signs were stabilized after blood transfusion and supportive cares for re-expansion pulmonary edema. The patient discharged from the hospital on 11^th in-hospital day after removal of the chest tube, and there had not been any recurrence of the pneumothorax for 10 months. We suggest that treatment strategy should be decided upon individually based on the patient's condition and clinical course of the disease.