• The Plant Pathology Journal
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• v.38 no.5
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• pp.490-502
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• 2022

Xanthomonas oryzae pv. oryzae (Xoo) causes bacterial leaf blight (BLB) disease in rice (Oryza sativa L.) and it is among the most destructive pathogen responsible for severe yield losses. Potential bacterial biocontrol agents (BCAs) with plant growth promotion (PGP) abilities can be applied to better manage the BLB disease and increase crop yield, compared to current conventional practices. Thus, this study aimed to isolate, screen, and identify potential BCAs with PGP abilities. Isolation of the BCAs was performed from internal plant tissues and rhizosphere soil of healthy and Xoo-infected rice. A total of 18 bacterial strains were successfully screened for in vitro antagonistic ability against Xoo, siderophore production and PGP potentials. Among the bacterial strains, 3 endophytes, Bacillus sp. strain USML8, Bacillus sp. strain USML9, and Bacillus sp. strain USMR1 which were isolated from diseased plants harbored the BCA traits and significantly reduced leaf blight severity of rice. Simultaneously, the endophytic BCAs also possessed plant growth promoting traits and were able to enhance rice growth. Application of the selected endophytes (BCAs-PGP) at the early growth stage of rice exhibited potential in suppressing BLB disease and promoting rice growth.

• Korean journal of applied entomology
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• v.31 no.3
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• pp.256-275
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• 1992

Insects are among the most important abiotic and biotic constraints to rice production. National rice research programs are in various stages in the development and implementation of integrated pest management (IPM) stratagies for rice insect control. Among the various control tactics, insect resistant cultivars are sought as the major tactic in rice IPM. Through the activities of interdisciplinary teams of scientists significant progress has been made in the development and release of insect resistant cultivars to farmers. Because of its compatibility with other control tactics insect resistance has proven to fit well into the IPM approach to rice insect control agents and minimize the need for insecticide applications. The development of biotypes which overcome the resistance in rice plants has been a significant constraint in the breeding of rice for resistance to insects. Most notable examples in Asia are the green leafhopper, Nephotettix virescens, brown planthopper, Nilaparvata lygens and the Asian rice gall midge, Orseolia oryzae. The current breeding stratege is to develop rice cultivars with durable resistance on which virulent biotypes cannot adapt. In spite of the significant progress made in the breeding of insect resistant cultivars there are still numerous important rice insect species for which host plant resistance as a control tactic has not been fully utilized. Advances in biotechnology provide promise of solving some of the problems that have limited the use of host plant resistance as a major tactic in the integrated management of rice insect pests.

• Korean Journal of Organic Agriculture
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• v.7 no.2
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• pp.99-106
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• 1999

In order to acquire microbial agents that can be utilized for biological control of bitter rot(Glomerella cingulata), the major airborne disease to apple, the effective microorganisms were isolated, tested for antagonistic activity to the pathogen. Through the screening of more than 1,000 species of microorganisms collected in nature, 11 species of antagonists were selected. On of the 11 species, one species designated as CH141 demonstrated outstanding activity. The bacterial strain, CH1141 exerted antagonistic efficiency of 65% on Glomerella cingulata. The CH1141 was identified as a bacterial strain to Bacillus subtilis based on morphology, culture conditions, and physiobiochemical characteristics.

• Applied Biological Chemistry
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• v.48 no.1
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• pp.34-39
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• 2005

There are various crop diseases in green houses that are caused by the cultural environments, especially high temperature and moisture. To solve the forementioned problems, farmers are overusing agricultural chemicals, causing other damages by the chemical residue. In this study, antagonistic bacteria as biological control agents were isolated to produce the environmentally-friendly crops for use in green houses. Eighteen species of antagonistic bacteria were totally isolated from the soil and plants in the Perilla fields, and AK-17 showed the highest activity among the isolates. According to the results of anti-fungal spectrum against several pathogens by AK-17, the antagonism effect of the isolates was remarkable against grey mold rot by Botrytis cinerea, sclerotinia rot by Sclerotnia sclerotiorum, and stem rot by Rhizoctonia solini. To evaluate the biological control effects of the isolates against the major diseases of Perilla, studies were carried out to evaluate the preventive and the curative effects of the diseases throughout the pot experiments. According to the forementioned experiments, the preventive and the curative effects by the isolates against sclerotinia rot were respectively showed as 55% and 92%. For the grey mold rot, those were 40% and 78%, respectively. As to the evaluation of the growth-promoting effect by AK-17, the length and the biomass of the tested plants were increased to 120% and to 164%, respectively. For the leaf numbers and area were respectively increased to 120% and 220%. Furthermore, AK-17 was identified as Burkhoderia sp. according to the results of physiological properties and genetic methods.

• Journal of Institute of Control, Robotics and Systems
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• v.12 no.3
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• pp.255-263
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• 2006

In the last decade, face analysis, e.g. face detection, face recognition, facial expression recognition, is a very lively and expanding research field. As computer animated agents and robots bring a social dimension to human computer interaction, interest in this research field is increasing rapidly. In this paper, we introduce an artificial emotion mimic system which can recognize human facial expressions and also generate the recognized facial expression. In order to recognize human facial expression in real-time, we propose a facial expression classification method that is performed by weak classifiers obtained by using new rectangular feature types. In addition, we make the artificial facial expression using the developed robotic system based on biological observation. Finally, experimental results of facial expression recognition and generation are shown for the validity of our robotic system.

• Journal of Microbiology and Biotechnology
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• v.24 no.6
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• pp.756-764
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• 2014

Apoptin, a chicken anemia virus-encoded protein, induces apoptosis in chicken or human tumor cells, localizing in their nuclei as opposed to the cytoplasm of non-transformed cells. The present study was undertaken to investigate whether ABPs1 could potentiate apoptin-induced apoptosis in HeLa cells. ABPs1 and the apoptin genes were successfully cloned into pIRES2-EGFP expression vector and expressed in HeLa cells. We report that ABPs1 augments apoptin cell growth inhibition in a concentration- and time-dependent manner. The DAPI staining and scanning electron microscopy observations revealed apoptotic bodies and plasma membrane pores, which were attributed to apoptin and ABPs1, respectively. Further, ABPs1 in combination with apoptin was found to increase the expression of Bax and to decrease the expression of survivin compared with either agent alone or the control. The apoptotic rate of HeLa cells treated with ABPs1 and apoptin in combination for 48 h was 53.95%. The two-gene combination increased the caspase-3 activity of HeLa cells. Taken together, our study suggests that ABPs1 combined with apoptin significantly inhibits HeLa cell proliferation, and induces cell apoptosis through membrane defects, up-regulation of Bax expression, down-regulation of survivin expression, and activation of the caspase-3 pathway. Thus, the combination of ABPs1 and apoptin could serve as a means to develop novel gene therapeutic agents against human cervical cancer.

• Journal of Life Science
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• v.18 no.6
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• pp.858-864
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• 2008

In the greenhouse fields for fruits and vegetables during the winter in Korea, there are serious damages by the sclerotium diseases due to the low temperature and humidity. This study was carried out to select an antagonic agent for the biological control of the sclerotium diseases. The 55 antagonic agents were selected from the rhizosphere in soil where the fruits and vegetables were cultivated in the green house fields, and strain AB02 among the tested isolates was estimated to be the strongest antagonist against the sclerotium disease. Using strain AB02, the antifungal spectrum was tested against 5 different plant pathogens. According to the results of the test, strain AB02 . showed the high antagonistic effect against Botrytis cinerea and Sclerotinia sclerotiorum. For the experiment of biological control against the sclerotium disease, it was estimated the suppression effect and the control effect by the strain in the pot experiment using the green perilla. According to the result of the pot experiments, the suppression effect was 40% and the control effect was 62%, respectively. For the stimulation effect of the tested plant growth by strain AB02 compared to the control, it was improved as 120% for the total length, 141% for the liveweight, 121% for the total number of leaves, 185% for the leaf area, and 327% for the liveweight of the root, respectively. Strain AB02 showing the antagonistic effect against the sclerotium disease and the stimulation effect for the plant growth was identified as Bacillus sp.

• Korean journal of applied entomology
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• v.40 no.3
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• pp.259-264
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• 2001

Toxicological studies of two potential biological control agents, the entomopathogenic nematode (Steinernema carpocapsae) and the symbiotic bacteria (Xenorhabdus nematophilus) were conducted against two beneficial insects and one mammal species. Two microbial agents varied in their toxicities between two insect species: an ant, Pristomyrmex pungens, and silkworm, Bombyx mori. In oral toxicity test, the symbiotic bacteria resulted in significant lethal [half lethal concentration of $1.4$\times$10^3$colony-forming units (cfu)/ml] on the ants, while they gave little lethal effect (half lethal concentration of more than $10^{8}$ cfu/ml) on the silkworms. The nematodes, however, gave significant lethal effect [half lethal concentration of 4 infected juveniles (IJs)/ml] on the silkworms, while they did little lethal effect (half lethal concentration of 150,000 IJs/ml) on the ants in topical assays. Both the nematodes and the bacteria did not give lethal effect to the albino rats, Rattus norvegicus, when they were fed orally into the rats. Also, any of these microbial agents were not detected in the internal organs of the treated rats.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.14 no.2
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• pp.595-609
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• 2020

In this study, we propose a decentralized mathematical model for predictive control of a system of multi-autonomous unmanned aerial vehicles (UAVs), also known as drones. Being decentralized and autonomous implies that all members make their own decisions and fly depending on the dynamic information received from other unmanned aircraft in the area. We consider a variety of realistic characteristics, including time delay and communication locality. For this flocking flight, we do not possess control for central data processing or control over each UAV, as each UAV runs its collision avoidance algorithm by itself. The main contribution of this work is a mathematical model for stable group flight even in adverse weather conditions (e.g., heavy wind, rain, etc.) by adding Gaussian noise. Two of our proposed variance control algorithms are presented in this work. One is based on a simple biological imitation from statistical physical modeling, which mimics animal group behavior; the other is an algorithm for cooperatively tracking an object, which aligns the velocities of neighboring agents corresponding to each other. We demonstrate the stability of the control algorithm and its applicability in autonomous multi-drone systems using numerical simulations.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2003.09a
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• pp.94-97
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• 2003

Various bioinformatics tools for biological data processing have been developed and most of them are available in public. Most bioinformatics works are carried out by a composite application of those tools. Several integration approaches have been proposed for easy use of the tools. This paper proposes a new multiagent system architecture to integrate bioinformatics tools in the perspective of workflow since the composite applications of tools can be regarded as workflows. For the easy integration, the proposed architecture employs wrapper agents for existing tools, uses XML-based messages in the inter-agent communication, and agents are supposed to extract necessary information from the received messages. This allows new tools to be easily added on the integration framework. The proposed method allows various control structures in workflow definition and provides the progress monitoring capability of the on-going workflows. We implemented a prototype system of the proposed architecture for annotating the genes of a bacterium called Sphingomonas Chungbukensis DJ77.