• The Plant Pathology Journal
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• 제36권3호
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• pp.204-217
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• 2020

In nature, plants are always under the threat of pests and diseases. Pathogenic bacteria are one of the major pathogen types to cause diseases in diverse plants, resulting in negative effects on plant growth and crop yield. Chemical bactericides and antibiotics have been used as major approaches for controlling bacterial plant diseases in the field or greenhouse. However, the appearance of resistant bacteria to common antibiotics and bactericides as well as their potential negative effects on environment and human health demands bacteriologists to develop alternative control agents. Bacteriophages, the viruses that can infect and kill only target bacteria very specifically, have been demonstrated as potential agents, which may have no negative effects on environment and human health. Many bacteriophages have been isolated against diverse plant-pathogenic bacteria, and many studies have shown to efficiently manage the disease development in both controlled and open conditions such as greenhouse and field. Moreover, the specificity of bacteriophages to certain bacterial species has been applied to develop detection tools for the diagnosis of plant-pathogenic bacteria. In this paper, we summarize the promising results from greenhouse or field experiments with bacteriophages to manage diseases caused by plant-pathogenic bacteria. In addition, we summarize the usage of bacteriophages for the specific detection of plant-pathogenic bacteria.

• 대한약침학회지
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• 제25권3호
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• pp.290-300
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• 2022

Objectives: This study was conducted to evaluate the safety of SU-Eohyeol pharmacopuncture (SUEP) by assessing its potential to cause chromosomal abnormalities in Chinese hamster lung cells (CHL/IC). Methods: A dose-curve was conducted to determine the highest dose of SUEP. Doses of 10, 5, 2.5, 1.25, 0.625, and 0.313% were used, and no cytotoxicity or SUEP precipitation was observed. SUEP doses of 10, 5, and 2.5%, with positive and negative controls, were used in a chromosome aberration test. Results: In this study, the frequency of abnormal chromosomal cells in the SUEP group did not show a statistically significant difference from that of the negative control group in short-term treatments with and without metabolic activation and the continuous treatment without metabolic activation. Compared with the negative control group, the positive control group had a significantly higher frequency of cells with structural chromosomal abnormalities. This test's results satisfied all conditions for determining the results. Conclusion: SUEP did not induce chromosomal aberrations under the conditions of this study. Other toxicity evaluations, safety studies in humans, and various clinical trials are required to evaluate the safety and efficacy of SUEP.

• 제어로봇시스템학회논문지
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• 제20권5호
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• pp.563-569
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• 2014

This article focuses on a hemispherical resonator gyro driven by the Coriolis effect. A hemispherical shell, called a resonator, is maintained in the resonance state by amplitude control and phase locking control. Parametric excitation has been used to control the amplitude. For rate measurement mode or FTR mode, nodal points have been kept to an amplitude of zero. Angular rate measurement has been demonstrated by rotating a resonator. Frequency mismatch between two stiffness principal axes is a major cause of low performance: vibrating pattern drift and reduced control effectiveness. This mismatch has been reduced significantly by the addition of small mass. A negative spring effect, which lowers resonance frequencies, has been verified experimentally.

• 한국미생물학회:학술대회논문집
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• 한국미생물학회 2002년도 추계학술대회
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• pp.40-50
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• 2002

Fruit fly, Drosophila melanogaster has developed efficient immune mechanisms to prevent microbial infection, which are consisted of cellular and humoral responses. During the systemic or local infection, two distinct pathways (Toll and Imd) play major roles in antimicrobial peptide synthesis. The Toll pathway is required to defend Gram-positive bacterial and fungal infections, whereas the Imd pathway is important in Gram-negative bacterial infection. We have shown that the infection of the opportunistic Gram-negative bacterium, Pseudomonas aeruginosa strain PA14 (PA14) into fly dorsal thorax can kill the flies within 48 h ($100\%$ mortality) in our optimized infection condition, suggesting that the PA14 strain can cause disease progress in fly model system. We found that flies carrying a constitutively activated mutant form of the Toll receptor $(Tl^{10b})$ showed increased resistance to P. aeruginosa infection and that flies carrying mutations in the Toll signaling pathway as well as in the Imd signaling pathway was more susceptible to PA14 infection. All these results imply that the Toll pathway might be important in the resistance to this pathogenic Gram-negative bacterial infection.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 F
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• pp.1914-1918
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• 1998

In the case of synchronous machines, certain power system disturbances cause the induced rotor current to assume negative values when no static converter is present. A converter, however. prevents negative current from flowing, so that overvoltages occur. The overvoltages can be effectively limited as crowbar circuit using GTO. This newly proposed crowbar circuit with current limiting resistor absorbs energy when overvoltage comes from power system repeatedly and is verified through experiment.

• 대한수의학회지
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• 제53권2호
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• pp.125-127
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• 2013

Canine Subcorneal pustular dermatosis (CSPD) represents a sterile, superficial, pustular skin disease of unknown cause but may be a variant of pemphigus foliaceus. A 7-year-old, intact female, mixed dog presented with 3-month history of pruritic multiple pustules and crusts. Direct smears from intact pustules revealed numerous nondegenerate neutrophils, some acantholytic cells, and bacterial culture was negative. Histologic examination of lesional skin showed subcorneal pustules filled with neutrophils and acantholytic cells. The direct immunofluorescence tests stained with IgG, IgA, IgM, C3 were negative. Oral administration of dapsone (1 mg/kg/q8h) was initiated and it was reduced to 1 mg/kg/q12h with good control of the lesions.

• Journal of Genetic Medicine
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• 제19권2호
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• pp.115-119
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• 2022

The 46,XX testicular disorder of sex development (DSD) is a rare condition in which 46,XX individuals develop testicular differentiation and virilization. Translocation of the sex-determining region Y (SRY) onto the X chromosome is the main cause of 46,XX testicular DSD, whereas dysregulation between pro-testis and pro-ovarian genes can induce SRY-negative 46,XX testicular DSD. Nuclear receptor subfamily 5 group A member 1 (NR5A1), a nuclear receptor transcription factor, plays an essential role in gonadal development in XY and XX embryos. Herein, we report the first Korean case of SRY-negative 46,XX testicular DSD with a heterozygous NR5A1 p.Arg92Trp variant. The patient presented with a small penis, bifid scrotum, and bilateral undescended testes. Whole exome sequencing revealed a heterozygous missense variant (c.274C>T) of NR5A1. Our case highlights that NR5A1 gene variants need to be considered important causative factors of SRY-negative non-syndromic 46,XX testicular DSD.

• 한국지반공학회논문집
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• 제23권10호
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• pp.57-64
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• 2007

현재 불포화토에 대한 많은 연구가 진행되어 왔고 최근 들어 많은 연구자들이 불포화지반의 안정성을 보다 합리적으로 판단하고 해석하기 위해 불포화상태를 고려한 연구의 필요성을 제기하여 왔다. 이를 위해서는 흡인력에 대한 전단강도의 증진효과를 정량화하고 이를 안정해석에 적용하는 것이 요구되고 있는 실정이다. 따라서 본 연구에서는 불포화 사질토의 전단강도 특성을 규명하기 일해서 국내에 널리 분포하는 화강풍화토 7가지를 대상으로 불포화 삼축압축시험을 수행하였으며, 결과치를 분석하여 강도특성을 규명하고자 한다.

• Nuclear Engineering and Technology
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• 제55권3호
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• pp.939-946
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• 2023

Comprehensive Research Facility for Fusion Technology (CRAFT) is an integration of different demonstrating or testing facilities, which aim to develop the critical technology or composition system towards the fusion reactor. Due to the importance and challenge of the negative ion based neutral beam injection (NNBI), a NNBI test facility is included in the framework of CRAFT. The initial object of CRAFT NNBI test facility is to obtain a H⁰ beam power of 2 MW at the energy of 200-400 keV for the pulse duration of 100 s. Inside the negative ion accelerator of NNBI system, the interactions of the negative ions with the background gas and electrodes can generate abundant stray electrons. The stray electrons can be further accelerated and dumped on the electrodes or eject from the accelerator. The stray electrons, including the ejecting electrons, cause the unwanted particle and heat flux onto the electrodes and the inner components of beamline (especially the temperature sensitive cryopump). The suppression of the stray electrons from the CRAFT accelerator is carried out via a series of design and simulation works. The paper focuses the influence of different magnetic field configurations on the stray electrons and the character of the ejecting electrons.

• International Journal of Contents
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• 제15권4호
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• pp.65-73
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• 2019

Social media is a massive dataset in which individuals' thoughts are freely recorded. So there have been a variety of efforts to analyze it and to understand the social phenomenon. In this study, Twitter was used to define the moments when negative perceptions of the Korean Meteorological Administration (KMA) were displayed and the reasons people were dissatisfied with the KMA. Machine learning methods were used for sentiment analysis to automatically train the implied awareness on Twitter which mentioned the KMA July-October 2011-2014. The trained models were used to validate sentiments on Twitter 2015-2016, and the frequency of negative sentiments was compared with the satisfaction of forecast users. It was found that the frequency of the negative sentiments increased before satisfaction decreased sharply. And the tweet keywords and the news headlines were qualitatively compared to analyze the cause of negative sentiments. As a result, it was revealed that the individual caused the increase in the monthly negative sentiments increase in 2016. This study represents the value of sentiment analysis that can complement user satisfaction surveys. Also, combining Twitter and news headlines provided the idea of analyzing the causes of dissatisfaction that are difficult to identify with only satisfaction surveys. The results contribute to improving user satisfaction with weather services by efficiently managing changes in satisfaction.