• Journal of Life Science
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• v.13 no.1
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• pp.110-117
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• 2003

A thermotolerant yeast strain, Saccharomyces cerevisiae KNU5377 (abbreviated as KNU5377, was exposed to inorganic acids including sulfuric, nitric and hydrochloric acid. As a stressor, each inorganic acid is very easily dissociated in water, resulting in lowering environmental pH. When compared with a reference S. cerevisiae ATCC24858, KNU5377 could overcome such a severe condition containing a final 0.4% concentration of sulfuric acid or nitric acid to grow at the overnight culture, but this reference could not. Additionally, this strain showed a surprisingly strong tolerance by surviving despite of exposure to the regime of 0.35% of hydrochloric acid for over 90 min and also to 0.6% of sulfuric acid for 30 min. On the contrary, both strains could not survive against a final 0.45% concentration of nitric acid. This strain KNU5377 could produce ethanol of 3% in 2 days by using the fermentation medium containing a final 0.3% concentration of sulfuric arid. Moreover, change into a final 0.2% concentration of sulfuric acid caused this strain to enhance fermentation productivity up to about 4.5% even at $40^{\circ}C$. In exposure to a final 0.2% of sulfuric acid for 60 min, trehalose was most accumulated within 30 min in KNU5377, and this suggested a cellular defense system led by this disaccharide was profitable for this strain to lead to no morphological changes.

• Korean Journal of Remote Sensing
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• v.29 no.2
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• pp.219-233
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• 2013

In this study, spatio-temporal variations of Land Surface Emissivity (LSE) of the three LSE data sets in the Asian-Oceanian regions were addressed. The MODerate Resolution Imaging Spectroradiometer (MODIS) LSE, Cooperative Institute for Meteorological Satellite Studies (CIMSS) LSE, and Kongju National Univ. (KNU) LSE data sets were used. The three data sets showed very similar emissivity in the Tibetan Plateau, desert in the Middle East and Australia, and low latitude regions irrespective of season. The emissivity of $12{\mu}m$ was systematically greater than that of $11{\mu}m$, in particular, in the Tibetan Plateau, desert over Middle East and Australia. In general, they showed a weak seasonal variation in the low latitude regions although the emissivity was different among them. However, the three data sets showed quite different spatial and temporal variations in the other regions of Asian-Oceanian regions. The KNU LSE showed a systematic seasonal variation with a high emissivity during summer and low emissivity during winter but the other two LSE data sets showed irregular seasonal variations without regard to the regions. And the annual mean correlations of $11{\mu}m$ and $12{\mu}m$ between KNU LSE and MODIS LSE (KNU LSE and CIMSS LSE; MODIS LSE and CIMSS LSE) were 0.423 and 0.399 (0.330, 0.101; 0.541, 0.154), respectively. The relatively low correlations and strong inter-month variations, in particular, in $12{\mu}m$, indicated that consistency in spatial variation was very low. The comparison results showed that caution should be given before operational use of the LSE data sets in these regions.

• Journal of Veterinary Clinics
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• v.28 no.1
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• pp.57-62
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• 2011

The shortage of transplantable kidneys has many efforts to regenerate bioartificial kidneys using transgenic animals and diverse kinds of scaffolds which are important tools for cell seeding. However, there are many limitations for clinical applications so far. Recently, decellularized bioscaffolds using animal organs come into spotlight because of its many superior advantages. In current study, we produced decellularized kidney bioscaffolds of pig which is an attractive animal as a clinical model for human. We decellularized pig kidneys with 1% SDS detergent solution using peristaltic pump systems for 12h. After decellularization process, the kidney bioscaffolds preserved intact 3D morphology including glomerular structure and almost DNA from pig was entirely removed. In addition, this process could preserve micro vascular network which is necessary for cell survival. Although, additional studies for recellularization and transplantation should be required, the decellular vascularized kidney bioscaffolds might have many potentials for kidney regeneration.

• Journal of Radiopharmaceuticals and Molecular Probes
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• v.7 no.2
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• pp.79-84
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• 2021

Radiopharmaceuticals are important for tumor diagnosis and therapy. To deliver a radiotracer at the desired target excluding non-targeted tissues is difficult The development of a targeted tracer that has a good clearance profile while maintaining high biostability and biocompatibility is key to optimizing its biodistribution and transport across biological barriers. Improving the hydrophilicity of radiotracers by PEGylation can reduce serum binding, allowing the tracer to circulate without retention and reducing its affinity for non-targeted tissues. In this study, we synthesized a new benzamido tracer (SnBz-PEG₃₆) with the introduction of a low molecular weight polyethylene glycol unit (PEG₃₆, ~2,100 Da). The tumor targeting efficiency and biodistribution of [¹³¹I]-Bz-PEG₃₆ or radiotracer-loaded liposomes were evaluated after their administration to normal mice or mouse tumor models including CT26 (xenograft) and 4T1 (xenograft and orthotopic). Most of the radiotracer was cleared out rapidly (1-24 h post-administration) through the kidney and there was little tumor uptake.

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 1987.10a
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• pp.255-257
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• 1987

• 한국지구물리탐사학회:학술대회논문집
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• 2011.10a
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• pp.95-96
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• 2011

• 한국지구물리탐사학회:학술대회논문집
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• 2010.10a
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• pp.29-32
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• 2010

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2008.11a
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• pp.111-116
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• 2008

지구온난화로 재난 재해가 날로 증가 되고 있으며, 그 규모도 대형화 되고 있는 추세이다. 재난 재해의 원인으로서는 자연적인 것도 있지만 인위적인 것이 큰 부분을 차지하고 있다. 이러한 재난 재해를 사전에 예방 및 통제를 목적으로 환경정보를 수집하여 위험상태를 판단하기위해 다양한 환경정보수집 무선통신기술에 대한 연구가 활발하게 진행되고 있다. 본 연구는 이러한 목적을 달성하기 위해 다양한 환경정보수집 및 시간 장소 설치 등에 많은 편리성 및 효율성을 갖으며, Ubiquitous Sensor Network(USN)기반요소가 되는 Sensor Network Node를 연구 개발하였고, 이를 이용하여 USN 환경감시 및 통제 네트워크를 구축하여 실험을 통하여 타당성을 입증하였다.

• Journal of Microbiology and Biotechnology
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• v.13 no.1
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• pp.85-89
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• 2003

The difference in the thermotolerance between Saccharomyces cerevisiae KNU5377 and ATCC24858 was compared by assaying the amounts of trehalose accumulated under growth and heat shock conditions. Both strains exhibited similar trehalose accumulation during the growth period, but an intrinsic thermotolerance was much higher in KNU5377 than in the control strain. This result implied that some strain-specific characteristics of KNU5377, other than trehalose accumulation, primarily were responsible fur its higher intrinsic thermotolerance. Heat shock at $43^{\circ}C$ for 90 min to the exponentially growing cells resulted in the maximum level of trehalose In both strains. Trehalose accumulated at least twice more in KNU5377 by the heat shock than in the control, due to the maintenance of its neutral trehalase activity even after the heat shock. Consequently, the Increase of acquired thermotolerance in both strains correlated with an increase in the trehalose content in each strain. In conclusion, KNU5377 exhibited a well-modulated trehalose-related mechanism to accumulate more trehalose by means of maintaining neutral trehalase activity after heat shock than the control strain, thereby contributing to its acquired thermotolerance.

• The Korean Journal of Mycology
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• v.51 no.1
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• pp.25-38
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• 2023

Three fungal strains belonging to the class Sordariomycetes were isolated from soil collected on Jeju Island and Gyeongsangbuk-do, Korea. They were identified as Diaporthe endophytica (KNU-JJ-1809), Faurelina indica (KNU-JJ-1830), and Trichoderma ivoriense (KNU-4-KH1). KNU-JJ-1809 produced beta conidia that were straight, curved, hyaline, smooth-walled, with a diameter of 16.5-25.0×0.6-1.7 ㎛. The conidia of strain KNU-JJ-1830 were hyaline to light green, thin, clavate, round, truncate base, had guttules at both ends, with a diameter of 2.5-5.2×1.7-3.8 ㎛. The conidia of strain KNU-4-KH1 were oblong or ellipsoidal, smooth-walled, greenish, with a diameter of 2.2-4.4×2.2-3.6 ㎛. Internal transcribed spacer regions, partial large subunit, translation elongation factor 1-alpha, β-tubulin, and calmodulin genes were used to confirm the strains, and their cultural and morphological characteristics. To our knowledge, this is the first report on D. endophytica, F. indica, and T. ivoriense in Korea.