• Title/Summary/Keyword: resistance change

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Characterization of a Novel Necrotic Response of Glycine max Line 'PI96188' to Xanthomonas axonopodis pv. glycines

  • Han, Sang-Wook;Choi, Min-Seon;Lee, Suk-Ha;Hwang, Duk-Ju;Hwang, Byung-Kook;Heu, Sung-Gi
    • The Plant Pathology Journal
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    • v.23 no.3
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    • pp.193-202
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    • 2007
  • Typical susceptible symptoms of the bacterial pustule disease caused by Xanthomonas axonopodis pv. glycines are pustule and chlorotic haloes that usually occur in leaves of Glycine max plants. The soybean genotype 'PI96188' showed an atypical response to all tested races X. axonopodis pv. glycines, accompanied with necrosis without chlorotic haloes on the underside of the necrotic symptoms. X. axonopodis pv. glycines 8ra grew to levels from 10 to 100 fold lower on PI96188 than on susceptible cultivar Jinjoo1, but 10-fold higher than on the resistant cultivar CNS. The chlorophyll content in PI96188 leaves remained unchanged until 12 days after bacterial infection. Ultrastructural observation showed that the infected leaf cells of PI96188 had intact normal chloroplasts compared to those of the susceptible cultivar Jinjoo1. Chloroplast degradation or the absence of chloroplasts in cells of the infected tissues was observed in Jinjoo1. Senescence-related ACS7 gene was significantly induced in PI96188 compared to those in Jinjoo1 at 2 days after inoculation. While photosynthesis-related rbcS gene showed the dramatic change in Jinjoo1, this gene was constitutively expressed in PI96188. However, expression of the defense-related genes, such as peroxidase and isoflavone synthase in the infected PI96188 leaves was similar to that in Jinjoo1. Together, these results suggest that the novel necrotic symptom in PI96188 is a kind of resistant response different from a typical hypersensitive response in the resistant genotypes.

Biomechanical Analysis at the Start of Bobsleigh Run in Preparation for the 2018 Pyeongchang Winter Olympics

  • Park, Seungbum;Lee, Kyungdeuk;Kim, Daewoong;Yoo, Junghyeon;Jung, Jaemin;Park, Kyunghwan
    • Korean Journal of Applied Biomechanics
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    • v.27 no.4
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    • pp.239-245
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    • 2017
  • Objective: The bobsleigh shoes used in the start section are one of the most important equipment for improving the competition. Despite the importance of the start section, there are no shoes that are specific for bobsleigh athletes in Korea and Korean athletes have to wear sprint spike shoes and practice the start instead of wearing bobsleigh shoes. The objective of the present study was to provide data for improving the performance of Korean bobsleigh athletes by investigating the differences in their split time, plantar pressure, and forefoot bending angle based on skill levels at the start of a run under the same conditions as training conditions. Method: Six Korean bobsleigh athletes were divided into two groups, superior (n=3) and non-superior (n=3). A digital speedometer measured the split time at the start; the Pedar-X system (Novel, Germany) measured plantar pressure. Plantar pressures and split times were measured as the athletes pushed a bobsleigh and sprinted at full speed from the start line to the 10-m mark on the bobsleigh track. An ultra-high-speed camera was used to measure the forefoot bending angle during the start phase. Results: Significant between-group differences were found in split times (p<.000; superior = 2.38 s, non-superior = 2.52 s). The superior group had a larger rearfoot (p<.05) contact area, maximum rearfoot force (p<.01), and a larger change in angles 3 and 4 (p<.05). Conclusion: At the start of a bobsleigh run, proper use of the rearfoot for achieving effective driving force and increasing frictional resistance through a wider frictional force can shorten start time.

Transition as a Theory and Practice: Transition Studies and Policies in Netherlands (이론과 실천으로서의 전환 : 네덜란드의 전환이론과 전환정책)

  • Jung, Byung Kul
    • Journal of Science and Technology Studies
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    • v.15 no.1
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    • pp.109-143
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    • 2015
  • For continuous and successful innovation, changes in innovation system are required and have been magnified as a new controversy. With high public interest in changes of innovation system, Transition theory and policy in Netherlands are now attracting attentions of many researchers and policymakers. Transition policy in Netherlands is distinguished from existing policies for fundamental system change in that take remarkably different views and methods. Typical examples of transition in Netherlands are such as sustainable energy transition, biodiversity and natural resource transition, sustainable agriculture transition, and sustainable transportation. Transitions in Netherlands are still in the early stage of it but several positive effects are witnessing. However some problems - linking theory and practice, ambiguity of transition concept, linking long-term vision and short-term, resistance of existing regime, implementation problem, diffusion of support, etc.- to be tackled are still remaining. In spite of those problems, many lessons can be drawn from them. To guide structural changes in innovation system into the right path and cope with lock-in problem by existing system and regime, we need to learn from Transition theory and policy in Netherlands.

Patterns of rpoC Mutations in Drug-Resistant Mycobacterium tuberculosis Isolated from Patients in South Korea

  • Yun, Yeo Jun;Lee, Jong Seok;Yoo, Je Chul;Cho, Eunjin;Park, Dahee;Kook, Yoon-Hoh;Lee, Keun Hwa
    • Tuberculosis and Respiratory Diseases
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    • v.81 no.3
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    • pp.222-227
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    • 2018
  • Background: Rifampicin (RFP) is one of the principal first-line drugs used in combination chemotherapies against Mycobacterium tuberculosis, and its use has greatly shortened the duration of chemotherapy for the successful treatment of drug-susceptible tuberculosis. Compensatory mutations have been identified in rpoC that restore the fitness of RFP-resistant M. tuberculosis strains with mutations in rpoB. To investigate rpoC mutation patterns, we analyzed 93 clinical M. tuberculosis isolates from patients in South Korea. Methods: Drug-resistant mycobacterial isolates were cultured to determine their susceptibility to anti-tubercular agents. Mutations in rpoC were identified by sequencing and compared with the relevant wild-type DNA sequence. Results: In total, 93 M. tuberculosis clinical isolates were successfully cultured and tested for drug susceptibilities. They included 75 drug-resistant tuberculosis species, of which 66 were RFP-resistant strains. rpoC mutations were found in 24 of the 66 RFP-resistant isolates (36.4%). Fifteen different types of mutations, including single mutations (22/24, 91.7%) and multiple mutations (2/24, 8.3%), were identified, and 12 of these mutations are reported for the first time in this study. The most frequent mutation involved a substitution at codon 452 (nt 1356) resulting in amino acid change F452L. Conclusion: Fifteen different types of mutations were identified and were predominantly single-nucleotide substitutions (91.7%). Mutations were found only in dual isoniazid- and RFP-resistant isolates of M. tuberculosis. No mutations were identified in any of the drug-susceptible strains.

Design of LED Lamp Circuits for UV Gel Nail (UV 젤 네일을 위한 LED 램프 회로 설계)

  • Kim, Phil Jung
    • Journal of the Institute of Electronics and Information Engineers
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    • v.53 no.10
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    • pp.133-137
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    • 2016
  • Use of UV gel for nail management have been increasing gradually. In order to develop an UV lamp necessary to UV gel, in this study, we was designed circuits of the UV-LED lamp. Power supply part that supplies constant power to the several UV-LEDs, was designed the circuit with the method of DC-DC converter. Taking into account the direction of the thumb nail and the position of the little finger nail, it was placed UV-LEDs. Input power of the power supply part was used as a battery voltage of 3.8[V]. The output voltage of the power supply part was appeared in approximately 3.1[V]. And in order to examine the state of change of the output voltage according to the amount of current consumption of UV-LEDs, after inserting of load resister, the output voltage was more than about 3.0[V] in the simulation results of the power supply part while changing the resistance value.

Electrochemical Catalytic Behavior of Cu2O Catalyst for Oxygen Reduction Reaction in Molten Carbonate Fuel Cells

  • Song, Shin Ae;Kim, Kiyoung;Lim, Sung Nam;Han, Jonghee;Yoon, Sung Pil;Kang, Min-Goo;Jang, Seong-Cheol
    • Journal of Electrochemical Science and Technology
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    • v.9 no.3
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    • pp.195-201
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    • 2018
  • To enhance the performance of cathodes at low temperatures, a Cu-coated cathode is prepared, and its electrochemical performance is examined by testing its use in a single cell. At $620^{\circ}C$ and a current density of $150mAcm^{-2}$, a single cell containing the Cu-coated cathode has a significantly higher voltage (0.87 V) during the initial operation than does that with an uncoated cathode (0.79 V). According to EIS analysis, the high voltage of the cell with the Cu-coated cathode is due to the dramatic decrease in the high-frequency resistance related to electrochemical reactions. From XPS analysis, it is confirmed that the Cu is initially in the form of $Cu_2O$ and is converted into CuO after 150 h of operation, without any change in the state of the Ni or Li. Therefore, the high initial cell voltage is confirmed to be due to $Cu_2O$. Because $Cu_2O$ is catalytically active toward $O_2$ adsorption and dissociation, $Cu_2O$ on a NiO cathode enhances cell performance and reduces cathode polarization. However, the cell with the Cu-coated cathode does not maintain its high voltage because $Cu_2O$ is oxidized to CuO, which demonstrates similar catalytic activity toward $O_2$ as NiO.

NDR Property and Energy Band Diagram of Nitro-Benzene Molecule Using STM (STM에 의한 니트로벤젠 분자의 NDR 특성과 에너지 밴드 구조)

  • Lee, Nam-Suk;Chang, Jeong-Soo;Kwon, Young-Soo
    • Proceedings of the KIEE Conference
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    • 2005.11a
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    • pp.139-141
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    • 2005
  • It is possble to study charge transfer property which is caused by height variation because we can see the organic materials barrier height and STM tip by organic materials energy band gap. Here, we investigated the negative differential resistance(NDR) and charge transfer property of self-assembled 4,4-Di(ethynylphenyl)-2'-nitro-1-(thioacetyl)benzene, which has been well known as a conducting molecule. Self-assembly monolayers(SAMs) were prepared on Au(111), which had been thermally deposited onto pre-treatment($H_{2}SO_{4}:H_{2}O_{2}$=3:1) Si. The Au substrate was exposed to a 1 mM/l solution of 1-dodecanethiol in ethanol for 24 hours to form a monolayer. After thorough rinsing the sample, it was exposed to a $0.1{\mu}M/1$ solution of 4,4-Di(ethynylphenyl)-2'-nitro-1-(thioacetyl)benzene in dimethylformamide(DMF) for 30 min and kept in the dark during immersion to avoid photo-oxidation. After the assembly, the samples were removed from the solutions, rinsed thoroughly with methanol, acetone, and $CH_{2}Cl_{2}$, and finally blown dry with $N_2$. Under these conditions, we measured electrical properties of self-assembly monolayers(SAMs) using ultra high vacuum scanning tunneling microscopy(UHV-STM). The applied voltages were from -1.50 V to -1.20 V with 298 K temperature. The vacuum condition is $6{\times}10^{-8}$ Torr. As a result, we found that NDR and charge transfer property by a little change of height when the voltage is applied between STM tip and electrode.

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Electrochemical Impedance Spectroscopy Analysis on the Dye-sensitized Solar Cell with Different $TiO_2$ thicknesses ($TiO_2$ 두께에 따른 염료감응형 태양전지의 전기화학적 임피던스 분석)

  • Kim, Hee-Je;Lee, Jeong-Gee;Seo, Hyun-Woong;Son, Min-Kyu;Kim, Jin-Kyoung;Prabalkar, K.;Shin, In-Young
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.58 no.12
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    • pp.2425-2430
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    • 2009
  • Dye-sensitized solar cell(DSC) is composed of a dye-adsorbed nanoporous $TiO_2$ layer on fluorine-doped tin oxide(FTO) glass substrate, electrolyte, and platinium doped counter electrode. Among these, a dye-absorbed nanoporous $TiO_2$ layer plays an important role in the performance of the DSC because the injected electrons from excited dye molecules move through this layer. And the condition of $TiO_2$ layer such as the morphology and thickness affects on the electron movement. Therefore, the performances and the efficiency of DSC change as the thickness of $TiO_2$ layer is different. Electrochemical Impedance Spectroscopy(EIS) is the powerful analysis method to study the kinetics of electrochemical and photoelectrochemical processes occurring in the DSC especially the injected electron movements. So we analyzed the DSCs with different $TiO_2$ thicknesses by using EIS to understand the influence of the $TiO_2$ thickness to the performance of the DSC clearly. Finally, we got the EIS analysis on the DSC with different $TiO_2$ thickness from the internal resistance of the DSC, the electron life time and the amount of dye molecules.

Geotechnical characteristics and consolidation properties of Tianjin marine clay

  • Lei, Huayang;Feng, Shuangxi;Jiang, Yan
    • Geomechanics and Engineering
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    • v.16 no.2
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    • pp.125-140
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    • 2018
  • Tianjin, which is located on the west shore of the Bohai Sea, is part of China's Circum-Bohai-Sea Region, where very weak clay is deposited. From the 1970s to the early $21^{st}$ century, Tianjin marine clay deposits have been the subject of numerous geotechnical investigations. Because of these deposits' geological complexity, great depositional thickness, high water content, large void ratio, excessive settlement, and low shear strength, the geotechnical properties of Tianjin marine clay need to be summarized and evaluated based on various in situ and laboratory tests so that Tianjin can safely and economically sustain more infrastructure in the coming decades. In this study, the properties of Tianjin marine clay, especially its consolidation properties, are summarized, evaluated and discussed. The focus is on establishing correlations between the geotechnical property indexes and mechanical parameters of Tianjin marine clay. These correlations include the correlations between the water content and the void ratio, the depth and the undrained shear strength, the liquid limit and the compression index, the tip resistance and the constrained modulus, the plasticity index and the ratio of undrained shear strength and the preconsolidation pressure. In addition, the primary consolidation properties of Tianjin marine clay, such as the intrinsic compression line (ICL), sedimentation compression line (SCL), compression index, $C_c$, coefficient of consolidation, $C_v$, and hydraulic conductivity change index, $C_{kv}$, are evaluated and discussed. A secondary consolidation property, i.e., the secondary compression index, $C_a$, is also investigated, and the results show that the ratio of $C_a/C_c$ for Tianjin marine clay can be used to calculate $C_a$ in secondary consolidation settlement predictions.

Effect of Extenders and Temperatures on Sperm Viability and Fertilizing Capacity of Harbin White Boar Semen during Long-term Liquid Storage

  • Zhou, J.B.;Yue, K.Z.;Luo, M.J.;Chang, Z.L.;Liang, H.;Wang, Z.Y.;Tan, J.H.
    • Asian-Australasian Journal of Animal Sciences
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    • v.17 no.11
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    • pp.1501-1508
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    • 2004
  • In this study the effect of extenders and temperatures on sperm viability and fertilizing capacity of boar sperm during long-term storage was investigated. Acrosomal integrity, membrane integrity, motility and hypo-osmotic resistance were evaluated by fluorescence and light microscopy. An in vitro fertilization test was performed to assess the fertilizing capacity of stored spermatozoa. The five diluents tested were ranked according to their ability to maintain sperm functional parameters and Zorlesco (ZO) extender with BSA or with PVA instead of BSA produced the best results. Zorlesco extender substituted with PVA (ZO+PVA) was found to maintain motility both at 15 and 20$^{\circ}C$. within 5 days of storage, but the quality of semen stored at 15$^{\circ}C$ decreased thereafter as compared to semen stored at 20$^{\circ}C$ Semen stored at 5$^{\circ}C$ demonstrated rapid loss of motility already within 24 h. Both fertilization and cleavage of semen stored at 20$^{\circ}C$ in ZO substituted with PVA instead of BSA did not change significantly until day 8 of storage. It is therefore concluded that PVA can be used to substitute for BSA and 20$^{\circ}C$ was more suitable than 15$^{\circ}C$ for boar semen storage, and in vitro fertilizing capacity of spermatozoa was maintained for at least 8 days in ZO+PVA at 20$^{\circ}C$.