• 한국진공학회:학술대회논문집
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• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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• pp.421.2-421.2
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• 2014

We report on the growth of ZnO nanorods (NRs) grown on graphite and silicon substrates via an all-solution process and characteristics of their heterojunctions. Structural investigations indicated that morphological and crystalline properties were not significantly different for the ZnO NRs on both substrates. However, optical properties from photoluminescence spectra showed that the ZnO NRs on graphite substrate contained more point defects than that on Si substrate. The ZnO NRs on both substrates showed typical rectification properties exhibiting successful diode formation. The heterojunction between the ZnO NRs and the graphite substrate showed a Schottky diode characteristic and photoresponse under ultraviolet illumination at a small reverse bias of -0.1 V. The results showed that the graphite substrate could be a good candidate for a Schottky contact electrode as well as a conducting substrate for electronic and optoelectronic applications of ZnO NRs.

• Fisheries and Aquatic Sciences
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• 제6권3호
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• pp.135-139
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• 2003

During routine survey of Pacific oyster (Crassostrea gigas) collected from Tongyoung area in southern coast of Korea, histological examination revealed that a intracellular microorganisms infected the digestive gland of the oyster. They infected hepatopancreatic cells extensively. The size of intracellular microorganism was of 45 to 86nm in diameter and 200nm to more thar 500nm in length. They were pleomorphic. The morphological characteristic of intracellular microorganisms lacked cell wall and was bounded by the plasma membrane. They contained typical prokaryotic ribosomes and fibrillar DNA-like strands. No additional internal structure has been observed. Based on the lack of cell wall and the cellular localization, the intracellular microorganism is considered as a Mycoplasma-like organism.

• 한국정밀공학회지
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• 제27권7호
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• pp.49-54
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• 2010

The cryogenic ball milling was performed on carbon nanotubes (CNTs) at an extremely low temperature to increase the dispersion of CNTs. The effects of milling speed and time on the deagglomeration and structural changes of CNTs were studied. FESEM was used to analyze the dispersion and the change of particle size before and after milling process. Transmission electron microscopic (TEM) analysis was also investigated the effect of cryogenic ball milling on the morphological characteristics of CNTs. The structural changes by the cryogenic ball milling process were further confirmed by x-ray diffraction (XRD) and Raman spectroscopic analysis. The results showed that the agglomeration of CNTs was significantly reduced and amorphous structure was observed at high milling speed. However, the milling time has no great effect on the dispersion property and structural change of CNTs compared with milling speed.

• Journal of Plant Biology
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• 제4권1호
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• pp.21-24
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• 1961

The strains of fungus which belong to Coniothyrium genus were isolated from leaf spoot of Yucca. The isolated strain can grow easily and forms characteristic colonies on Saido's soy agar. There are definite differences, according to other authors, (By Miyake et Hara 1911) Pycnidio-spore are usually formed ellipsoidal, dark brown, 4$\times$2. 5-4. $O\mu$ in size, whereas isolated strains are globose, yellowish brown, 2.8-4.2$\mu$ in diameter. The positive inoculation test can be attained by burned petridish method, preserving it in incubator at 28$^{\circ}C$, and the pycnidio-spore can be reisolated from the inoculated portion. (Photo.7) Up to the present day there is no report for leaf spot of Yucca caused by Coniothyrium sp.. Comparing the writer's isolate with those fungi described(leaf spot of alloe, rose canker and elm canker etc.) hitherto, there are no accordance in the symptom and especially in morphological charactgers and Pathogenicitys.

• Plant Resources
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• 제6권3호
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• pp.188-194
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• 2003

Present studies were carried out to produce tetraploid plants by colchicine treatment using seeds, seedlings and shoot tips of Platycodon grandiflorum in Campanulaceae. The most successful colchicine treatment for tetraploid production in P. grandiflorum was soaking treatment using 0.01 and 0.5% colchicine solution for 1 hour and 12 hours, respectively. Morphological characteristics of both diploid and tetraploid were similar, but tetraploid plants had more leaves. Compared to diploid, tetraploid had the larger stomata, but less number of stomata. Fresh weight of tetraploids was 20∼40% heavier than that of diploid.

• Macromolecular Research
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• 제13권5호
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• pp.385-390
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• 2005

The electrospinning process is a fascinating method to fabricate small nanosized fibers of diameter several hundred nanometers. Surfactant-polymer solutions were prepared by adding poly(vinyl alcohol) (PVOH) to distilled water with cationic, anionic, amphoteric, and non-ionic surfactants. Average diameter of the electrospun PVOH fibers prepared from PVOH solution was over 300 nm, and was decreased to 150 nm for the mixture of PVOH/amphoteric surfactant. To explain the formation of ultra fine fiber, the characteristic properties in a mixture of PVOH/surfactant such as surface tension, viscosity, and conductivity were determined. In this paper, the effect of interactions between polymers with different classes of surfactants on the morphological and mechanical properties of electrospun PVOH nonwoven mats was broadly investigated.

• Archives of Pharmacal Research
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• 제19권2호
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• pp.91-94
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• 1996

In the course of a search for antitumor agents, we found that the extract of Curcuma longa was effective in inducing apoptosis or programmed cell death (PCD) in human myeloid leukemia cells (HL-60). Active compounds for PCD were isolated from the hexanic extraction of the rhizome of Curcuma longa. With the several chromatographies, and spectral data, they were identified as ar-turmerone and $\beta-atlantone$. The present results demonstrate that the exposure of human myeloid leukemia HL-60 cells to clinically achievable concentrations of arturmerone (TU) or .$\beta-atlantone$(AT) produced internucleosomal DNA fragmentation of approximately 200 base-pair multiples, and the morphological changes characteristic of cells undergoing apoptosis or PCD. This findings suggest that these agents may exert their antitumoral activity, in part, through induction of apoptosis(PCD).

• 전기학회논문지
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• 제60권3호
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• pp.654-661
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• 2011

This paper is about a personal identification algorithm using an ECG that has been studied by a few researchers recently. Previously published algorithm can be classified as two methods. One is the method that analyzes of ECG features and the other is the morphological analysis of ECG. The main characteristic of proposed algorithm can be classified the method of analysis ECG features. Proposed algorithm adopts DSTW(Down Slope Trace Wave) for extracting ECG features, and applies SVM(Support Vector Machine) to training and testing as a classifier algorithm. We choose 18 ECG files from MIT-BIH Normal Sinus Rhythm Database for estimating of algorithm performance. The algorithm extracts 100 heartbeats from each ECG file, and use 40 heartbeats for training and 60 heartbeats for testing. The proposed algorithm shows clearly superior performance in all ECG data, amounting to 93.89% heartbeat recognition rate and 100% ECG recognition rate.

• 대한세포병리학회지
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• 제18권2호
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• pp.175-177
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• 2007

A case of Burkitt lymphoma diagnosed through fine needle aspiration cytology is described, A 66-year-old man presented with lymphadenopathy on the right cervical neck and axillary area. An ultrasonogram and CT scan for the cervical neck showed a multiple variable sized lymphadenopathy with pericapsular invasion and necrotic foci, Fine needle aspiration cytology (FNAC) of the cervical lymph nodes revealed very cellular and necrotic smears consisting of diffusely scattered intermediate monotonous round cells, tingible body macrophages and many mitotic figures. Histological features of the excised lymph nodes showed the classic morphological features of Burkitt lymphoma. Recognition of the characteristic cytological features can suggest the possibility of Burkitt lymphoma.

• 한국균학회지
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• 제47권3호
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• pp.271-274
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• 2019

Between August and September 2017, zonate leaf spots with severe defoliation were observed on Parthenocissus tricuspidata in Gimcheon, Korea. The initial symptoms included water-soaked, gray to grayish brown, circular or irregular-shaped leaf spots. As the disease progressed, the spots enlarged, coalesced, and became cream-colored with characteristic target-shaped rings, leading to leaf blight and premature defoliation. Based on cultural and morphological characteristics, the fungus associated with the symptoms was identified as Grovesinia moricola. The identity of this fungus was confirmed by analyzing sequences of the internal transcribed spacer region of ribosomal DNA. The pathogenicity of the isolate was demonstrated by artificial inoculation. To our knowledge, this is the first report of G. moricola occurring on P. tricuspidata globally as well as in Korea.