• Korean Journal of Agricultural Science
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• v.45 no.4
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• pp.561-573
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• 2018

Oomycetes are known to secrete a vast arsenal of effectors that modulate the host defense system as well as facilitate establishing a parasitic infection in plants. In recent years, tremendous progress has been made in the field of effectromics based on studies of oomycetes, especially the cytoplasmic family of RXLR effectors. Yet, the biology of the RXLR effector family is still poorly understood. There has been a consensus regarding the structure of the RXLR motif in the mycologist community. However, the function of the RXLR motif is still unclear. First, different models have suggested that the role of the RXLR motif is either in translocation to a target destination inside a host cell or in the cleavage of itself followed by secretion. Second, recent studies have suggested different functional models for the RXLR motif. According to a widely accepted model, the RXLR motif is directly involved in the translocation of effectors to target sites. In contrast, a new study has proposed that the RXLR motif is involved in secretion rather than translocation. Thus, this review is an attempt to summarize the recent advances made in the functional analysis of the N-terminal domain of RXLR effectors.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2004.11a
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• pp.531-534
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• 2004

Cutting work of the concrete pile is an important task to chsh a part of pile head which is compressed with more than $800kgf/cm^{2}$. It is usually performed by a crusher and three to four skilled workers. llecent analysis results of the pile cutting work reveal that it frequently makes a lot of cracks which significantly reduce the strength of the pile and is labor-intensive work. The primary objective of this study is to propose the end-effector which can effectively break PHC Pile without any longitudinal cracks before developing an automated pile cutting machine having unified grinder and crusher parts. It is anticipated that the development of the automated pile cutting machine would be able to bring improvements in safety, productivity, quality as well as cost saving.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.37 no.1
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• pp.89-95
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• 2013

This study investigates a parallel manipulator that can move over two parallel sliders and in which the end-effector of the manipulator can be adjusted arbitrarily. Through the direct and inverse kinematics of the manipulator, position equations are derived. These equations represent the relationship between the positions of the sliders and the position of the end-effector. The Jacobian matrices of the direct and inverse kinematics are obtained by these equations. By using the condition number defined from these matrices, the local performance index of the manipulator is proposed. By using the simulation results of the performance index, we find that the manipulator can smoothen movements in only one quadrant and that the distribution of the maximal performance index is affected by the ratio of the length of links and the orientation of the end-effector.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.257-257
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• 2022

Late blight, caused by the hemibiotrophic oomycete pathogen Phytophthora infestans, has been the most important disease limiting potato production worldwide. P. infestans undergo major population shifts in agricultural systems via the successive emergence and migration of asexual lineages. The phenotypic and genotypic bases of these selective sweeps are largely unknown but management strategies need to adapt to reflect the changing pathogen population. Here, we used molecular markers to divide the 86 South Korea isolates into six clonal lineages: KR_1_A1, KR_2_A2, SIB-1, US-11, SIB-1 like, and KR-2 like. We documented the emergence of a new lineage, termed SIB-1 like, and KR-2 like, and their rapid replacement of other lineages to exceed 35% of the pathogen population across South Korea. Genome analyses of the Korean P. infestans populations revealed extensive genetic polymorphism, particularly in effector genes. Importantly, SIB-1 like isolates carry an intact Avr8 effector gene that triggers resistance in potato carrying the corresponding R immune receptor gene R8 cloned from Solarium demissum. These findings point toward a strategy for deploying genetic resistance to mitigate the impact of the SIB-1 like lineage and illustrate how pathogen population monitoring, combined with genome analysis, informs the management of devastating disease epidemics. Further study is being done on pathogenicity of the SIB-1 like isolates on cultivated potatoes and changes in expression patterns of disease effector genes within the SIB-1 like isolates

• Biotechnology and Bioprocess Engineering:BBE
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• v.10 no.5
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• pp.444-450
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• 2005

Epidermal growth factor (EGF) activates many intracellular effector molecules, which subsequently influence the expression levels of many genes involved in cell growth, apoptosis and signal transduction, etc. In this study, the early response of gene expressions due to EGF treatment was monitored using oligonucleotide DNA microarrays in rat schwannoma cell lines. An immunoblotting experiment showed the successful activation of EGF receptors and an effector protein, STAT5, due to EGF treatment. The microarray study showed that 35 genes were significantly induced and 2 were repressed within 60 min after the treatment. The list of induced genes included early growth response 1, suppressor of cytokine signaling 3, c-fos, interferon regulatory factor 1 and early growth response 2, etc. According to the microarray data, six of these were induced by more than 10-fold, and showed at least two different induction patterns, indicating complicated regulatory mechanisms in the EGF signal transduction.

• Journal of Ocean Engineering and Technology
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• v.34 no.3
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• pp.180-193
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• 2020

In this study, the end-effector tracking performance of a manipulator installed on a remotely operated vehicle (ROV) for autonomous underwater intervention is verified. The underwater manipulator is an ARM 7E MINI model produced by the ECA group, which consists of six joints and one gripper. Of the six joints of the manipulator, two are revolute joints and the other four are prismatic joints. Velocity control is used to control the manipulator with forward and inverse kinematics. When the manipulator approaches a target object, it is difficult for the ROV to maintain its position and posture, owing to various disturbances, such as the variation in both the center of mass and the reaction force resulting from the manipulator motion. Therefore, it is necessary to compensate for the influences and ensure the relative distance to the object. Simulations and experiments are performed to track the trajectory of a virtual object, and the tracking performance is verified from the results.

• Biotechnology and Bioprocess Engineering:BBE
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• v.9 no.3
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• pp.229-235
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• 2004

The influence of sucrose on in vitro growth, chlorophyll content, and rubisco/rubisco activase were studied in tobacco leaves. The most pronounced effect on in vitro growth and the chlorophyll content was found at 4% sucrose. The rubisco content increased with increasing concentrations of sucrose, but a point was reached beyond which the increasing concentrations of sucrose caused an inhibition of this enzyme. The rubisco activity showed patterns of change similar to the rubisco content. These data suggest that sucrose may have an affect on the activation and induction of rubisco and that sucrose can be both a positive effector and negative effector depend on its concentration. The degree of intensity of 55 and 15 kD polypeptides, which were identified as the large and small subunit of rubisco, respectively, by SDS-PAGE analysis at 4% sucrose was significantly higher than that of other treatments, indicating that sucrose had an effect on both subunits. We subsequently examined whether the rubisco content and activity of being induced by sucrose is associated with rubisco activase. The rubisco activase content at 4% sucrose was higher than that of other treatments. A similar change pattern was also observed in the activity of rubisco activase. The intensity of two 52 and 51 kD polypeptide bands at 4% sucrose was higher than that of corresponding bands of other treatments. The stimulatory and inhibitory effects of rubisco by sucrose seemed to be caused by rubisco activase.

• 제어로봇시스템학회:학술대회논문집
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• 1992.10a
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• pp.953-958
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• 1992

This paper deals with the solution of inverse kinematics of the industrial FANUC robot with IBM PC386. The inverse kinematics of FANUC robot cannot be solved by the algebraical method, because arm matirix T$_{6}$ is very complex and 6-joint angles are associated with the position and the approach of end-effector. Instead we fuund otehr 5-joint angle by and algebraical method after finding .THETA.$_{1}$ value by a numerical method.d.

• Microbiology and Biotechnology Letters
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• v.21 no.6
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• pp.594-599
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• 1993

In the course of screening for microbial metabolites employing human cancer cell line, we identified a mycelial extract of Streptomyces sp. 1365, which are effective on growth inhibition and morphological change of MCF-7, human breasr cancer cell line. By repeased column chromatography and recrystallization process, yellow needle crystals were obtained as an active compound and identified as resistomycin by spectral analysis.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.166.2-166.2
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• 2003

Garlic (Allium sativum) has been used as a general food and a remedy in Oriental for a long time. Since garlic compounds have been also shown to inhibit growth of tumors and to modulate the activity of carcinogenesis, the effects of allicin on growth and survival in human gastric epithelial cells were evaluated by cell viability, cell cycle analysis and DNA fragmentation. Protein levels of cytochrome C, Bcl-xL, Bax and AIF were detected by Western blotting. Effects of recombinant VacA on caspase proteases activity were also determined. (omitted)