• Research in Plant Disease
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• v.23 no.1
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• pp.1-18
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• 2017

Pseudomonas syringae pv. actinidiae, the causal agent of bacterial canker, is currently causing severe economic losses to kiwifruit production worldwide. The pathogen has affected green-fleshed kiwifruit cutlivars and yellow-fleshed kiwifruit cultivars since 1988 and 2006 in Korea, respectively. In recent years, the biovar 3 strains of P. syringae pv. actinidiae were introduced through imported contaminated pollens and have rapidly spread to neighboring kiwiruit orchards by secondary infection, leading to outbreaks of bacterial canker and tremendous damages on yellow- and red-fleshed kiwifruit cultivars. In this review, we summarize the various management practices of bacterial canker of kiwifruit such as disease escaping, cultural practices, blocking of dissemination, early diagnosis, eradication of inoculum sources, chemical control, and trunk injection on the basis of our research works and field experiences and important research products conducted during the last three decades in the world. Finally, we propose a manual for the efficient management of the disease that can be practically utilized at the farmers' orchards in order to keep kiwifruit vines healthy in the future.

• The Plant Pathology Journal
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• v.31 no.2
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• pp.108-114
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• 2015

Curvularia lunata is an important maize foliar fungal pathogen that distributes widely in maize growing area in China, and several key pathogenic factors have been isolated. An yeast two-hybrid (Y2H) library is a very useful platform to further unravel novel pathogenic factors in C. lunata. To construct a high-quality full length-expression cDNA library from the C. lunata for application to pathogenesis-related protein-protein interaction screening, total RNA was extracted. The SMART (Switching Mechanism At 5' end of the RNA Transcript) technique was used for cDNA synthesis. Double-stranded cDNA was ligated into the pGADT7-Rec vector with Herring Testes Carrier DNA using homologous recombination method. The ligation mixture was transformed into competent yeast AH109 cells to construct the primary cDNA library. Eventually, a high qualitative library was successfully established according to an evaluation on quality. The transformation efficiency was about $6.39{\times}10^5$ transformants/$3{\mu}g$ pGADT7-Rec. The titer of the primary cDNA library was $2.5{\times}10^8cfu/mL$. The numbers for the cDNA library was $2.46{\times}10^5$. Randomly picked clones show that the recombination rate was 88.24%. Gel electrophoresis results indicated that the fragments ranged from 0.4 kb to 3.0 kb. Melanin synthesis protein Brn1 (1,3,8-hydroxynaphthalene reductase) was used as a "bait" to test the sufficiency of the Y2H library. As a result, a cDNA clone encoding VelB protein that was known to be involved in the regulation of diverse cellular processes, including control of secondary metabolism containing melanin and toxin production in many filamentous fungi was identified. Further study on the exact role of the VelB gene is underway.

• Journal of Korean Society on Water Environment
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• v.33 no.3
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• pp.348-358
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• 2017

The process of evaluating and selecting the best available techniques presents various characteristics for each country. In the case of EU, BAT is selected through TWG meeting after first screening, mass and energy balance, impact assessment and decision support process. Korea has proposed four principles to select BAT that can be carbon neutral for each environmental infrastructure in order to reduce greenhouse gas emissions. In order to evaluate and select the best available technique, it is necessary to differentiate the method according to whether it is a technique generally applied at the current workplace, whether it is a single technique or a combination technique, and whether it is a technology technique or management technique. In the case of a single technique, it should be evaluated whether it is a technique applied in the workplace, excessive cost, superior environmental technique over BAT, and secondary environmental pollution. In the case of multiple techniques, it is necessary to examine whether the emission standards are met and whether the pollutants can be treated at the same level as BAT. In the case of BAT candidates for management techniques, whether or not they contribute directly or indirectly to lowering the emission level of pollutants can be an important evaluation item. In the case of environmental techniques that are not generally applied in the workplace, it is recommended that the following 8 steps be carried out, including those prescribed by law. In the first stage, the list of performance evaluation factors is listed. In the second stage, the level of disposal of pollutants and the level of satisfaction with standards are listed. In the third stage, the environmental evaluation elements are listed. In the fourth stage, Is to list the economic evaluation elements, step 6 is to list the pollution and accident prevention evaluation factors, step 7 is the quantitative evaluation of the technical working group, and step 8 is BAT confirmation through deliberation of the central environmental policy committee.

• Journal of the Korean Regional Science Association
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• v.8 no.1
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• pp.1-29
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• 1992

The major purpose of this paper is to examine two closely related issues. An attempt is made here to examine internationally high land price in Korea from the perspectives of market fundamentals (MF) and bubble theory, respectively. Another theoretical issue, whether land speculation can result in market failure, is also examined. It has been concluded that the primary causes for the rapid increases in land prices in Korea, could be found in the perspective of MF. (1) The financial intermediaries has been controlled by the government since 1960s. Real Interest rates in the commercial banks has been controlled at the level of zero or sometimes negative; scarce financial resources has been rationed by the government. The governmental control of the bands has also resirained the development of securities market. Money, which can not find the appropri opportunity for saving in financial market, moves to land market. (2) Socially created land value, based on rapid economic gorwth and big public investment, has been appropriated mainly by the private: The effective tax rate of land holding tax has been under 0.02 percent; Real Estate Capital Galns Tax has, in fact, affected few persons, mainly because examptions and preferential taxation have been widely permitted. (3) The government has ploaced severe limitations on rural-to-urban land conversion, although the demand for urban uses has repidly grown. All factors above caused the cyclical land speculation. This, in turn, created the myth that land prices will inevitably continue to rise. Based on the myth, the growing bubble in land price has been created. This is the secondary reason for high land price relative to income in Korea. It is also shown that it is possible that speculation in land results in market failure because land is fixed in quantity and can be used for production and speculation purposes simultaneously.

• Journal of Korean Society of Steel Construction
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• v.21 no.1
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• pp.83-91
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• 2009

Buckling Restrained Braces (BRBs) show good seismic behavior. They do not dissipate energy, however, when they are subjected to minor earthquakes or wind. Hybrid Buckling Restrained Braces (H-BRBs), which can improve the wind performance of the BRB system, are a kind of hybrid damper system composed of a viscoelastic damper and BRBs. In this paper, two H-BRB specimens with different cores were experimentally investigated to ensure the structural behavior of the H-BRB system in an elastic range. The axial deformation of the primary resisting system was compared with that of the secondary resisting system, and the equivalent damping ratio of the H-BRBs was estimated. It was concluded that H-BRBs with double shear dampers show good structural behavior and are applicable to tall buildings, to improve the building performance at a comfortable level.

• Korean Journal of Veterinary Service
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• v.26 no.2
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• pp.135-144
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• 2003

Fowl typhoid is a septicemic disease of turkeys and chickens. The antigen is Salmonella(S) gallinarum, which cross-reacts with S pullorum because of common antigen. The organism is maintained in the ovary of carrier birds and transmitted vertically in the york. It is also transmitted horizontally through feces and broken eggs. The symptoms are weakness, drowsiness, wing drooping, hyperexcitability, paresis and diarrhea. In the many cases, the birds are found dead in the morning before any symptoms have been noticed. this experiment was carried out to investigate the characteristics of S gallanarum and scrutinized about the control systems. 1. Fowl typhoid was came about in the winter than the other seasons. The average of mortality was 46.3%. And it was came about not only adult poultry but also chicks. 2. S gallinarum was isolated from liver and spleen in infected chickens. Total isolated strains were 60. 3. The organisms were all extinct at 60$^{\circ}C$, 30mins. 4. A survival rate was higher in underground water than a secondary distilled water. It was detected in underground water until 30 days. 5. When being exposed to the solar light, it became extinct almost within 24 hours. 6. It was survived in a refrigerator until 12 months. 7. It was extinct among 5 mins in 0.1% phenol and 2% formalin. 8. When the cultured organism fluid was inoculated in SD-rat abdominal cavity, rat died within 24 hours. 9. Pullorum-typhoid related program must disciplines in order to destroy the fowl typhoid, and breeding system must be converted to cage system.

• Journal of Korean Society of Water and Wastewater
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• v.28 no.6
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• pp.657-668
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• 2014

Under Korea's Enforcement Decree of the Framework Act on Environmental Policy amended in 2013, total organic carbon (TOC) is newly added as water quality parameter to assess organic pollution in water and aquatic ecosystem. To meet the TOC requirement and improve quality of effluent discharged into public watershed, it is also necessary to develop standards for TOC in effluent from public sewage treatment works (PSTWs). In this study, we reviewed the characteristics and removal efficiency of TOC in influent and effluent of PSTWs. The study found that phosphorus treatment process removed not only soluble phosphorus but also a portion of TOC remaining after the secondary treatment process. TOC concentration in effluent from PSTWs operated in tandem with industrial wastewater treatment work was higher due to influx of insoluble substances from the industrial wastewater treatment work. In order to lay a foundation for the management of TOC from PSTWs, it is necessary to carry out research on TOC from different perspectives. For example, studies on the generation mechanism of TOC and the impact of TOC on drinking water resources, assessment of effluent qualities through monitoring, and development of measures to control TOC for the preservation of aquatic ecosystem are needed.

• Economic and Environmental Geology
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• v.13 no.4
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• pp.215-227
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• 1980

The rock units of Goesan area in the Ogcheon metamor phic terrain established on the basis of field criteria should be redefined into following sequence. Based on shear senses in secondary small structures which are usually observable in the investigated area, the stratigraphy can be lithologically divided into the lower pelite, pebbly mudstone, upper pelite, quartzite and psammite unit in ascending order. This conclusion is in discordance with a previous opinion; Munjuri formation and Guryongsan formation may be equivalent to upper pelite unit, Iwonri formation and Hwanggangri formation to pebbly mudstone. From this, it may be inferred that isoclinal overturned folds repeatly occur in the area. The uranium bearing coaly thin layers in upper pelite unit have relatively broad exposures in Deogpyeongri block of Goesan area along culmination zone in the central part of the investigated area. It is believed that structural feature in the block recognized complexly refolded synform plunging to southwest. Mineralogical and radiometric studies were made on 135 representative samples from the Ogcheon Group of Korea. The mineralogy of all black slate samples is qualitatively similar but quantitatively ·different. The uranium distribution in the studied area show approximately log normal. Uranium in the black slates of the Ogcheon Group was deposited together under same physico-chemical environmental conditions. The chemical and geological factors that controlled the abundance of organic carbon and iron oxides also controlled the uranium content. The relationship of the major components to uranium can be expressed by the following regression equation: $Log(U\times10^4+1)$= 1.70999-0.00367(quartz)0.00512(micas)-0.00930 (other silicates)+0.01911 (iron oxides)-0.03389(other opaques)+0.02062(organic carbon).

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.4
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• pp.512-520
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• 2016

Breast cancer is the most common malignancy in women, and lymphedema is one of the most common postoperative complications of breast surgery. Exercises are usually prescribed to prevent this occurrence. On the other hand, conflicting results regarding the effects and timing of such exercises have been reported. This study reviewed systematically the contemporary literature, peer-reviewed publications, and web sites of professional organizations that examined exercise for lymphedema prevention or therapy to determine the effects of exercise on lymphedema providing the best evidence for the treatment of patients. Exercise or training groups have strategies that appear to reduce the development of secondary lymphedema and altering its progression compared to the control group. Advances in cancer treatment, cancer and exercise research, and lymphedema management require physicians to have a basic understanding of the current evidence to provide the appropriate patient education and specialist referral.

• Mass Spectrometry Letters
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• v.2 no.1
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• pp.1-7
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• 2011

China's rapid economic growth has resulted in significant environmental side effects. Therefore, China has been interested in reducing her dependence on foreign oil and gas by developing technologies needed for hydrogen, in addition to her increasing energy mix of nuclear and renewable energy form, such as solar and wind power. There are three isotopes of hydrogen, i.e. protium (P or H), deuterium (D), and tritium (T). Both deuterium and tritium are important materials in nuclear fuel cycle industry. Tritium is one of the critical radioactive nuclides. Planning for and implementing contamination control as a part of normal operation and maintenance activities is an important function in any hydrogen facility, especially tritium facility. The development of hydrogen isotopes analysis is the key issues in this area. Mass spectrometry (MS) with medium (about 600) and high resolution (> 1,400) is commercially available; however, the routine analysis of hydrogen isotopes is done with low-resolution MS (< 200) in China. This paper summarizes the progress of MS measurement technology for hydrogen isotope abundance in China, focusing on our lab's research program and technical status. An analyzing method has been introduced for accurate measurement of tritium abundance in the H.D.T system by low resolution MAT-253 MS. The quotient of compression ratio coefficient is determined by building up equipment for laboratory-scale preparation of secondary standard gases and by considering the difference in sensitivity between hydrogen isotopes. The results show that the measured value is reproducible within the relative error range of 0.8% for gas samples of different tritium abundance.