• Journal of Microbiology and Biotechnology
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• 제21권11호
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• pp.1123-1126
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• 2011

The IncP plasmid R995 has been a useful self-transmissible, broad-host-range vector for a number of applications including the recombinase/conjugation-based cloning of large genomic DNA segments. However, R995 derivatives (or related plasmids) expressing a wide range of different resistance markers and Flp recombinase target sites do not exist in the literature. In addition, documented strategies for applying such plasmids in cloning applications that take advantage of conjugation for the convenient isolation and recovery of constructs are extremely limited. Here, we report a new series of R995 plasmids with alternative markers to increase options for applications in backgrounds already expressing resistance to a particular antibiotic(s). These R995 plasmids have been engineered to contain FRT sites that can be used for recombinase-based cloning. We demonstrate the utility of this approach by cloning 20 kb regions from the Salmonella Typhimurium and Escherichia coli genomes and by cloning DNA from an exogenous plasmid source. To our knowledge, this represents the first systematic engineering of an intact, self-transmissible IncP plasmid with a series of alternative antibiotic markers and FRT sites.

• International Journal of Industrial Entomology and Biomaterials
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• 제23권2호
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• pp.215-221
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• 2011

To establish an indoor-rearing system for the Large Copper butterfly, $Lycaena$ $dispar$ and the Small Copper butterfly, $Lycaena$ $phlaeas$, the effect of temperature, photoperiod and host plants on larval development was investigated. The larvae of $Lycaena$ $dispar$ fed on $Rumex$ $crispus$, whereas the larvae of $Lycaena$ $phlaeas$ ate both $Rumex$ $crispus$ and $Rumex$ $acetosa$. The duration of the larval period of $Lycaena$ $dispar$ was 13.8 days on $R.$ $crispus$ and that, of $Lycaena$ $phlaeas$ was 15.9 days and 15.2 days on $R.$ $acetosa$ and $R.$ $crispus$ respectively. Laboratory experiments show that the Large Copper larvae are able to feed on other $Rumex$ species without harming their overall survival and can utilize these alternative host plants at least as efficiently as their natural host plant. This result suggests that plant chemistry is not responsible for their lack of utilization of the alternative host plants in the wild. Host plant choice by ovipositing females was measured with the two alternative hosts. $Lycaena$ $dispar$ preferred $R.$ $crispus$ to $R.$ $acetosa$, wheareas $Lycaena$ $phlaeas$ preferred $R.$ $acetosa$ to $R.$ $crispus$. Temperature has been proposed as an important determinant of developmental rate, lifespan and mortality in invertebrates. As temperature increased, length of the developmental period gradually decreased. The developmental period of the Large Copper larvae was 11.0 days and 28.5 days at $30^{\circ}C$ and $17.5^{\circ}C$, respectively.

• The Plant Pathology Journal
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• 제31권3호
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• pp.245-251
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• 2015

Alternative hosts increase the difficulty of disease management in crops because these alternate hosts provide additional sources of primary inoculum or refuges for diversity in the pathogen gene pool. Agropyron cristatum (crested wheatgrass), Bromus inermis (smooth bromegrass), Pascopyrum smithii (western wheatgrass), Stipa viridula (green needlegrass), and Thinopyrum intermedium (intermediate wheatgrass), commonly identified in range, prairie, verge, and soil reclamation habitats, serve as additional hosts for Pyrenophora tritici-repentis, the cause of tan spot in wheat (Triticum aestivum L.). A. cristatum (five lines), B. inermis (seven lines), P. smithii (four lines), S. viridula (two lines), and T. intermedium (six lines) were tested for their reactions to 30 representative P. tritici-repentis isolates from races 1-5. Plants were grown until the two-three-leaf stage in a greenhouse, inoculated individually with the 30 isolates, held at high humidity for 24 h, and rated after 7 days. All lines developed lesion types 1-2 (resistant) based on a 1-5 rating scale. Also, leaves from an additional plant set were infiltrated with two host selective toxins, Ptr ToxA as a pure preparation and Ptr ToxB as a dilute crude culture filtrate. All lines were insensitive to the toxins. Results indicate that these grass hosts have a limited or nonsignificant role in tan spot epidemiology on wheat in the northern Great Plains. Additionally, the resistant reactions demonstrated by the grass species in this research indicate the presence of resistance genes that can be valuable to wheat breeding programs for improving wheat resistance to P. tritici-repentis.

• 한국가금학회지
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• 제38권4호
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• pp.275-284
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• 2011

As the world population grows and developing countries become more affluent, the global consumption of meat will increase by more than 50% within the next 10 years. Confronting the increased demand for poultry food products are emerging field diseases, increasing regulatory bans of antimicrobial growth promoters, high-density growth conditions, and waste management. Although biotechnology offers solutions to some of these challenges, basic studies are needed to better understand the complex interaction between the intestinal microbiome, host immunity and the environment. This presentation will focus on emerging strategies to enhance gut immunity and to decrease economic losses due to poultry diseases. This presentation will highlight recent developments in coccidiosis research and provide information on host immunity, immunomodulation, and the latest advances in dietary and nutritional approaches against coccidiosis. Such information will magnify our understanding of host-parasite biology, mucosal immunology, and design of future nutritional interventions and vaccination strategies for coccidiosis.

• 한국중재학회지:중재연구
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• 제27권1호
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• pp.131-160
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• 2017

When any investment dispute arises, the investor has to exhaust the local remedies available in the host state, and according to the agreement between the parties, the investor is filed to the ICSID arbitral tribunal to seek arbitral awards. At this time, if the arbitral tribunal decides that the investment agreement has been violated, it normally demands the host state to provide financial compensations to the investor for economic loss. According to the rules of the investment agreement, the host state is supposed to fulfill the arbitral awards voluntarily. If it is unwilling to provide financial compensations according to the arbitral awards, however, the investor may ask the domestic court of the host state for the recognition and enforcement of arbitral awards. In addition, if the host state is unwilling to fulfill arbitral awards on account of state immunity, the investor may ask his own country (state of nationality) for diplomatic protection and urge it to demand the fulfillment of arbitral awards. Effectiveness for pecuniary damages, a means to solve problems arising in the enforcement of investment arbitral awards, is found to be rather ineffective. For such cases, this study suggests an alternative to demand either a restitution of property or a corrections of violated measures subject to arbitral awards.

• International Journal of Industrial Entomology and Biomaterials
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• 제6권2호
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• pp.125-132
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• 2003

Uzi fly (Exorista bombycis Louis) is one of the major larval endo-parasitoid of silkworm (Bombyx mori). It causes extensive damage to sericulture industry. The application of synthetic organic pesticides has tremendous impact on minimizing pest population but their overuse and frequent misuse and high sensitivity towards the silkworms, has forced the entomologists to search for alternatives to chemical control, which is safe to silkworm, environment and farm workers. Biological control continues to offer exciting possibilities for the control of fly pest population. It is environmentally safe alternative to chemical control and offering a long-term protection. Several potential hymenopteran parasitoids have been screened. Among successful natural enemies, Nesolynx thymus, Trichomalopsis apanteloctena, Trichopria sp., Brachymeria lasus, Pediobius sp., Spalangia sp., Spilomicrus karnatakensis and Dhirhinus sp. are important. It is essential to predict accurately the efficacy of these natural enemies in a new habitat prior to its introduction. The important desirable attributes of these potential parasitoids viz., host searching capacity, specificity, power of increase and fitness and adaptability of the parasitoid in new environment has been recorded. Results of the host parasitoid interaction indicate that the aging of the host function as a factor that influence the host finding efficiency of the parasitoid. It is highly scored with 15-20 hrs old pupa of the host. However, aging of the parasitoid does not significantly affect it. The sex ratio is female biased which is advantageous from biological control point of view, Biological suppression methods involving conservation and utilization of natural enemies have been discussed in detail.

• Journal of Oral Medicine and Pain
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• 제43권1호
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• pp.16-20
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• 2018

Graft-versus-host disease (GVHD) is frequent complications of hematopoietic stem cell transplantation. In the chronic GVHD (cGVHD), the oral cavity is the most commonly affected region. The clinical manifestations include erythema, ulceration, lichenoid-hyperkeratotic change in oral mucosa, dry mouth, and limitation of mouth opening. The initial treatment strategy of oral cGVHD patients is topical corticosteroid therapy in various formulation. However, corticosteroid resistance appears in some patients. We report a case of a 25-year-old male patient with oral cGVHD, who has resistance to topical corticosteroid medication, treated with 0.03% tacrolimus ointment and low-dose doxycycline. The patient showed subjective and objective improvement without side effect.

• Journal of Microbiology and Biotechnology
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• 제29권3호
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• pp.392-400
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• 2019

Chondroitin, the precursor of chondroitin sulfate, which is an important polysaccharide, has drawn significant attention due to its applications in many fields. In the present study, a heterologous biosynthesis pathway of chondroitin was designed in a GRAS (generally recognized as safe) strain C. glutamicum. CgkfoC and CgkfoA genes with host codon preference were synthesized and driven by promoter Ptac, which was confirmed as a strong promoter via GFPuv reporter assessment. In a lactate dehydrogenase (ldh) deficient host, intracellular chondroitin titer increased from 0.25 to 0.88 g/l compared with that in a wild-type host. Moreover, precursor enhancement via overexpressing precursor synthesizing gene ugdA further improved chondroitin titers to 1.09 g/l. Chondroitin production reached 1.91 g/l with the engineered strain C. glutamicum ${\Delta}L-CgCAU$ in a 5-L fed-batch fermentation with a single distribution $M_w$ of 186 kDa. This work provides an alternative, safe and novel means of producing chondroitin for industrial applications.

• 한국응용곤충학회지
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• 제34권3호
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• pp.278-286
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• 1995

쌀바구미에 적응된 기생봉 Anisopteromalus calandrae를 대체기주인 팥바구미에서 누대 사육하면서 기생천적의 대체기주에 대한 적응과 그의 과정을 조사하였다. A. calandrae기 대체기주에 적응, 안정된 생활사 특성을 보이기까지 2세대가 경과하였다. 성충수명은 단축되어 1세대에서 8.7일을 보였으나 2세대 이후에는 5.7~7.3일의 범위를 나타내었으며 총 산란수는 1세대에서 29.3$\pm$7.7에서 2세대 이후 43.9~68.2의 범위로 증가하였다. 따라서 내적 자연 증가율, 순증가율은 증가하였으며, 개체군 배가 기간은 짧아졌다. 팥바구미에 대한 탐색효율은 적응 전후에 유의한 차이를 보이지 않았으나 탐색효율의 변이계수가 감소하는 현상을 보여 탐색행동이 안정됨을 암시하였다. A. calandrae는 팥바구미에 적응된 이후에도 쌀바구미에 대한 탐색효율이 감소되지는 않았다.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.140.2-141
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• 2003

Among over-wintering small brown planthoppers, population of the rice stripe virus (RSV)-viruliferous insects was surveyed throughout the country in late April of 2003 by using DAS-ELISA. Averaged population of the RSV-viruliferous insects in this year was 2.1％, which was lower than that of last year of 3.7％. However, the insect population in Seoul, Incheon and Kyeonggi areas were relatively high showing 6.7％, 6.2％ and 2.6％, respectively. Based on the survey results, it was expected that overall occurrence of RSV on rice could be decreased in this year, except certain areas. Ovarial transmission rate of RSV by the insects on diseased rice samples collected from 10 areas ranged from 22.2％ to 77.8％. Among 35 graminous weed species collected from rice fields in Ganghwa and Kimpo in 2002 and 2003, common reed and formosens were found to be infected by RSV. The result indicates that those weeds are potential alternative natural hosts of the RSV Further studies on ecological and pathological impacts of the alternative natural host of RSV are being processed.