• Journal of Korean Society of Forest Science
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• v.86 no.1
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• pp.80-86
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• 1997

The objective of this study was to investigate how resistant poplar hybrid makes compensation to ozone stress. Growth, net assimilation rate and initial Rubisco activity were investigated. This study elucidates the physiological mechanisms associated with ozone sensitivity and resistance in 3 selected $F_2$ hybrids, a family originating from a cross between Populus trichocarpa${\times}$P. deltoides. Open-top chambers were used. Ozone concentrations varied from 90 to 115 ppb for 126 days, 6 to 9 hours in a day. This study tested the hypothesis that resistant poplar hybrid maintains the biomass production to ozone exposure via increased net assimilation rate and Rubisco activity. Growth, biomass, net assimilation rate and initial Rubisco activity were generally reduced by ozone treatment. In the tree parts, root under ozone stress was the most sensitive part. Reduced allocation of photosynthates to root growth might be due to increased respiratory demands for maintenance and repair of aboveground tissue damaged by ozone stress. Maintenance or increases remaining leaves in photosynthetic rates and Rubisco activity in resistant clone in response to ozone treatment were the results of biological compensation to ozone stress.

• Korean Journal of Ichthyology
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• v.33 no.3
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• pp.157-166
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• 2021

Three specimens, presumed to be natural hybrids between Rhodeus notatus and R. ocellatus, were collected from Onyangcheon Stream area, Jwabu-dong, Asan-si, Chungcheongnamdo, the Republic of Korea, and morphological and phylogenetic analyses were performed to clearly identify their parent species. The body color of the three natural hybrids was light greenish-brown on dorsal side, and the size of red area on the upper front of the dorsal fin and the outer margin of the anal fin generally showed intermediate characters between the parent species, R. notatus and R. ocellatus. Among the measurement and meristic characters, the ratio of prepectoral length and preanal length in the standard length, and the ratio of snout length, interorbital width, length of caudal peduncle and depth of caudal peduncle in the head length, and the number of longitudinal row scales were analyzed as the unique characters of natural hybrids. In the rag1 gene of nuclear DNA, the three natural hybrids were analyzed to be reflected all the single nucleotide polymorphism sites between R. notatus and R. ocellatus, and in the phylogenetic tree using the cytb gene of mitochondrial DNA, they formed the same genetic clade as R. notatus. Therefore, three specimens, presumed to be natural hybrids analyzed in this study were identified as interspecific hybrids between female R. notatus and male R. ocellatus.

• The Journal of the Korea Contents Association
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• v.5 no.1
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• pp.157-167
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• 2005

In this paper, we propose a new phantom protection method for multi-dimensional index structures. The proposed method uses a hybrid approach of predicate locking and granular locking mechanisms. The proposed mechanism is independent of the types of multi-dimensional index structures, i.e., it can be applied to all types of index structures such as tree-based, file-based and hash-based index structures. Also, it achieves low development cost and high concurrency with low lock overhead. It is shown through various experiments that the proposed method outperforms existing phantom protection methods for multi-dimensional index structures.

• Journal of Plant Biology
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• v.8 no.1_2
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• pp.11-18
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• 1965

Since Taquet's first discovery of wild P. yedoensis at Mt. Halla, Korea, in 1908, its morphological chracteristics and question of origin of cultivated yedoensis have given controversies to the botanists. Takenaka, through his experiments on the hybridity of cultivated P. yedoensis, recently holds the opinion that P. yedoensis might have originated in Izu peninsula, Japan. The author presents the summarized report on the wild P. yedoensis and its putative parents based on his 2 years' investigated carried out at Mt. Halla during his breeding experiment of genus Prunus. The species of cherry tree used in the present investigation were identified by Prof. Mankyu Park and Mr. Jonghyu Pu, Korean taxonomists. 1) Wild cherry trees which grow wild in Mt. Halla and whose blooming season is April are mostly P. subhirtella var. pendula form. ascendens and P. donarium P. yedoensis is rare in number, around 10 individuals, having been found in a half century. 2) Individuals of wild yedoensis are variable in some of their morphological characteristics. This is, also, true in other species of Prunus. 3) Wild yedoensis whose vigorous growth, sterility, and rarity in number suggest hybrid origin, has intermediate characteristics between the P. subhirtella and P. donarium. 4) Due to the abnormal weather of the island and various environmental factors such as havbitats, some of the early-blooming subhirtella and late-blooming donarium would bloom at the same time, giving these two species the changes to cross. 5) Wild yedoensis is slightly different in some of its quantitative characters from cultivated species.

• Journal of Plant Biotechnology
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• v.45 no.3
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• pp.236-241
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• 2018

Lilium is a perennial bulbous plant belonging to the liriotypes genus. Our aim was to study the phylogenetic relationships of the Lilium family. Two varieties of Lilium ledebourii, 44 varieties of the gene bank, and one variety from the Tulipa family served as the out group. In order to study the diversity between lilium masses, ITS regions were used to design the marker. The results showed that the guanine base is the most abundant nucleotide. Relatively high conservation was observed in the ITS regions of the populations (0.653). Phylogenetic analysis showed that sargentiae and hybrid varieties are older than other varieties of the Lilium family. Also, the location of L. ledebourii varieties (Damash and Namin) was identified in a phylogenetic tree by using the ITS marker. Overall, our research showed that ITS molecular markers are very suitable for phylogenetic studies in the Lilium family.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.51 no.4
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• pp.404-410
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• 2018

Takifugu rubripes, T. chinensis, T. pseudommus and an unidentified species were morphologically and genetically studied. Morphology was compared using external morphology and the genetic analysis was conducted using mitochondrial DNA cytochrome oxidase I (COI) and cytochrome b (Cyt b). The morphological characteristics of T. rubripes, T. chinensis and T. pseudommus were confirmed, as reported previously. The unidentified species was confirmed to have the characteristics of T. rubripes and T. chinensis. The COI sequences of the four species were 99-100% similar; genetic distance was d=0.0000 and Cyt b genetic distance was d=0.0000-0.00834. Species in the phylogenetic tree belonging to the same group could not be classified genetically. In conclusion, the unidentified species was considered to be a hybrid between T. rubripes and T. chinensis.

• Journal of KIISE:Software and Applications
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• v.31 no.4
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• pp.488-497
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• 2004

This paper describes the hybrid document summarization using the indicative summarization and the query-based summarization. The learning models are built from teaming documents in order to extract topic phrases. We use Naive Bayesian, Decision Tree and Supported Vector Machine as the machine learning algorithm. The system extracts topic phrases automatically from new document based on these models and outputs the summary of the document using query-based summarization which considers the extracted topic phrases as queries and calculates the locality-based similarity of each topic phrase. We examine how the topic phrases affect the summarization and how many phrases are proper to summarization. Then, we evaluate the extracted summary by comparing with manual summary, and we also compare our summarization system with summarization mettled from MS-Word.

• The Journal of Korea Robotics Society
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• v.11 no.2
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• pp.41-50
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• 2016

This paper describes the effect of a robot cognitive rehabilitation program on cognitive functions for the elderly with mild cognitive impairment, and compares it with traditional cognitive therapy programs. Three experiment groups including cognition therapy group, robot cognitive rehabilitation group, and hybrid group have been sampled and one comparative group has been organized for this research. 32 old people whose ages are between 61 and 88 with mild cognitive impairment participated in the programs with an admission of W care hospital. According to the program results, the cognitive therapy program alone had shown a positive effect on the attention function, and the robot cognitive rehabilitation program alone had a positive effect on the total intelligence and memory function. However, a simultaneous operation with both programs had shown a positive effect on the three intelligence areas such as total, basic, and management quotients as well as attention and memory functions as subsidiary factors. This paper has verified that the proposed robot cognitive rehabilitation program makes a positive effect on a cognitive function and plays a complementary role with traditional cognitive therapy programs.

• Journal of Korean Society of Forest Science
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• v.95 no.5
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• pp.516-523
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• 2006

Marginal soils such as BRlS (Beach Ridges Interspersed with Swales) soils and ex-tin mining land make up approximately 0.5 million ha or about 2% of Malaysia's land area. In the coastal areas of the east coast of Peninsular Malaysia impoverished sandy BRIS dominates the landscape with most lying idle as there is no national management plan for their utilization. A field study was carried out to see whether mycorrhizal application had any effect on the growth of three exotic Acacia spp., i.e. Acacia auriculiformis, A. mangium and Acacia hybrid (A. auriculiformis ${\times}$ A. mangium) on BRIS soils. Two types of mycorrhizal inoculum, namely, a commercially available arbuscular mycorrhizal inoculum marketed as $MycoGold^{TM}$ and an indigenous ectomycorrhizal Tomentella sp. inoculum were tested. In the initial six months, height growth of all three tree species inoculated with the arbuscular mycorrhizal inoculum was significantly improved compared to the ectomycorrhizal inoculated and uninoculated control plants. The mycorrhizal effect was not evident thereafter and repeated application of the arbuscular mycorrhizal inoculum may be necessary for continued growth enhancement. Of the three species, A. mangium had the highest relative height growth rate over the 24 months on BRlS soils.

• Parasites, Hosts and Diseases
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• v.57 no.1
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• pp.43-47
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• 2019

Anaplasma marginale and A. platys were detected and characterized (16S rDNA sequence analysis) from dairy and indigenous cattle, and the latter in domestic dogs in Vietnam. A phylogenetic tree was inferred from 26 representative strains/species of Anaplasma spp. including 10 new sequences from Vietnam. Seven of our Vietnamese sequences fell into the clade of A. marginale and 3 into A. platys, with strong nodal support of 99 and 90%, respectively. Low genetic distances (0.2-0.4%) within each species supported the identification. Anaplasma platys is able to infect humans. Our discovery of this species in cattle and domestic dogs raises considerable concern about zoonotic transmission in Vietnam. Further systematic investigations are needed to gain data for Anaplasma spp. and members of Anaplasmataceae in animal hosts, vectors and humans across Vietnam.