• Title/Summary/Keyword: Function Taxonomy

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A Review on the Microstructures and Taxonomy of the Acartia bifilosa (Crustacea: Copepoda) in Kyeonggi Bay, Yellow Sea

  • Shim, Moon-Bo;Choi, Joong-Ki
    • Journal of the korean society of oceanography
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    • v.31 no.1
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    • pp.37-42
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    • 1996
  • Acartia bifilosa has been classified as Rostratae group of Acartia by the characteristic of having the rostral filament. However, we have found that A. bifilosa does not have any rostrum. Therefore, A. bifilosa should be classified as Arostratae group. For the first time, we have observed that this species has only one genital pore in the genital segment. Two spermathecal canals are looped in lateral view as well as ventral view. We have also observed two thin, very short filaments and minute apertures on the anterio-ventral part of the top of the head. The function of the filaments need to be investigated.

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Phytopythium and Pythium Species (Oomycota) Isolated from Freshwater Environments of Korea

  • Nam, Bora;Choi, Young-Joon
    • Mycobiology
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    • v.47 no.3
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    • pp.261-272
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    • 2019
  • Oomycetes are widely distributed in various environments, including desert and polar regions. Depending upon different habits and hosts, they have evolved with both saprophytic and pathogenic nutritional modes. Freshwater ecosystem is one of the most important habitats for members of oomycetes. Most studies on oomycete diversity, however, have been biased mostly towards terrestrial phytopathogenic species, rather than aquatic species, although their roles as saprophytes and parasites are essential for freshwater ecosystems. In this study, we isolated oomycete strains from soil sediment, algae, and decaying plant debris in freshwater streams of Korea. The strains were identified based on cultural and morphological characteristics, as well as molecular phylogenetic analyses of ITS rDNA, cox1, and cox2 mtDNA sequences. As a result, we discovered eight oomycete species previously unknown in Korea, namely Phytopythium chamaehyphon, Phytopythium litorale, Phytopythium vexans, Pythium diclinum, Pythium heterothallicum, Pythium inflatum, Pythium intermedium, and Pythium oopapillum. Diversity and ecology of freshwater oomycetes in Korea are poorly understood. This study could contribute to understand their distribution and ecological function in freshwater ecosystem.

Electron-Morphometric Classification of the Native Honeybees from Korea Part V. Cluster Analysis by Canonical Function Score (한국산 재래꿀벌의 전자계량형태학적 분류 V. 정준판별함수값을 이용한 군분석)

  • Kwon Yong Jung;Huh Eun Yeop
    • Animal Systematics, Evolution and Diversity
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    • v.8 no.2
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    • pp.189-200
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    • 1992
  • In the present investigation, some cluster analyses were done for each population of the native honeybee workers(Apis cerana), which were selected for 15 different localities in spring and 16 in summer from Korea. In this analysis, the seasonal segregation was perfectly revealed by both Ward's and the average linkage between groups methods, whereas, it did not necessarily revealed any systematic relationship between geographical groups.

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Taxonomy of Asian Geranium L.(Geraniaceae) based on fruit and seed morphology

  • Park, Seon-Joo;Park, Hong-Duok
    • Journal of Environmental Science International
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    • v.11 no.2
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    • pp.121-130
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    • 2002
  • Compare to investigate the taxonomic utility of infragenera system and interspecific of Asian Geranium, we examined the fruit and seed morphology from 35 taxa. The fruit shape and seed's dispersal way did so that may divide subgenus or some part section to do could reason evolutionary trends. That is, at seed dispersal, the awns of section Geranium of subgenus Geranium, ramains attached at the top of rostrum, though fairy easily broken off, because seed increases awn's elasticity by diffusive way, it is long characteristic seed\`s dispersal distance, and subgenus Robertium observed that seed dispersal distance is short because it is no awn's elasticity by way that seed dispersal is gone as awn drops with rostrum. Also, section Geranium of subgenus Geranium and subgenus Robertium act role that awn keeps temporarily breed swerving with mericarp instead of bristle because section Tuberosa of subgenus Geranium is not bristled function that keep temporarily breed because mericarp bristled on base at seed dispersal do while. Therefore, is thought that is talon that when consider formation's development and function regarding this seed dispersal function, subgenus Geraniuum evolves more than subgenus Robertium. Seed morphology can divide by 2 subgenera(Geranium, Robertium) according to pattern of seed coat. and Seed's morphology characteristic(whole shape, color, form of seed apical and base, micropyle area, hilum area, chalaza, and position of seed hilum area), can distinguish some species, but is thought that is not reasonable as for discernment characteristic form and nature by repetition of characteristic form and nature. Especially, infrasection do in fruit and seed's morphology that is handling in this research that know to argue classification system and relationship by repetition of characteristic form and nature difficult. To all reliable truth, cytological, ecological, embryology, and molecular genetics research about talon is considered that should be achieved section Geranium that do not handle yet.

Hydrocarbon patterns in Cleisostoma scolopendrifolium (Orchidaceae) as a key mechanism for pollination

  • SON, Hyun-Deok;YUN, Seon A;KIM, Seung-Chul;IM, Hyoung-Tak
    • Korean Journal of Plant Taxonomy
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    • v.50 no.2
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    • pp.148-153
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    • 2020
  • Cleisostoma scolopendrifolium is an orchid species solely pollinated by the male bee Megachile yasumatsui. Although C. scolopendrifolium is an endangered species in Korea, little is known about its pollination mechanisms or the profiles of its chemical attractants. This study provides evidence that the Cleisostoma orchid attracts male bees as pollinators by mimicking female mating signals. We found 13 hydrocarbons in the Cleisostoma orchid flower presumed to be involved in sex pheromone mimicry: five alkanes (tricosane, pentacosane, heptacosane, nonacosane, and hentriacontane), compounds of cuticular hydrocarbons which function as chemical cues for the recognition of mates and species in social insects; and eight alkenes ((z)-9-tricosene, (z)-9-pentacosene, (z)-11-pentacosene, (z)-9-heptacosene, (z)-11-heptacosene, (z)-9-nonacosene, (z)-11-nonacosene, and (z)-11-hentriacontene) which serve as sex pheromones in several insects. We suggest that these hydrocarbons play a key role in the pollination mechanism between Cleisostoma orchids and Megachile bees.

Transposable Elements and Genome Size Variations in Plants

  • Lee, Sung-Il;Kim, Nam-Soo
    • Genomics & Informatics
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    • v.12 no.3
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    • pp.87-97
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    • 2014
  • Although the number of protein-coding genes is not highly variable between plant taxa, the DNA content in their genomes is highly variable, by as much as 2,056-fold from a 1C amount of 0.0648 pg to 132.5 pg. The mean 1C-value in plants is 2.4 pg, and genome size expansion/contraction is lineage-specific in plant taxonomy. Transposable element fractions in plant genomes are also variable, as low as ~3% in small genomes and as high as ~85% in large genomes, indicating that genome size is a linear function of transposable element content. Of the 2 classes of transposable elements, the dynamics of class 1 long terminal repeat (LTR) retrotransposons is a major contributor to the 1C value differences among plants. The activity of LTR retrotransposons is under the control of epigenetic suppressing mechanisms. Also, genome-purging mechanisms have been adopted to counter-balance the genome size amplification. With a wealth of information on whole-genome sequences in plant genomes, it was revealed that several genome-purging mechanisms have been employed, depending on plant taxa. Two genera, Lilium and Fritillaria, are known to have large genomes in angiosperms. There were twice times of concerted genome size evolutions in the family Liliaceae during the divergence of the current genera in Liliaceae. In addition to the LTR retrotransposons, non-LTR retrotransposons and satellite DNAs contributed to the huge genomes in the two genera by possible failure of genome counter-balancing mechanisms.

Toward a Conceptualization of Clothing Price Perception: A Taxonomy of shopping Behavior (의복가격지각의 다차원성에 관한 연구: 구매행동 유형화를 중심으로)

  • 이규혜;이은영
    • Journal of the Korean Society of Clothing and Textiles
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    • v.26 no.6
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    • pp.877-888
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    • 2002
  • Price is a product attribute, which is determined by the function of the producing cost and profit. It is also identified as one of the most important components of the marketing mix. For consumers, price is an always-existing cue, definite evaluation criteria, and easily accessible information in the purchasing process. Considering the concept of the clothing-price in a comprehensive perspective encompassing economic, psychological and marketing perspectives, a theoretical model was developed. The model includes souses and dimensions of price perception and related behaviors. Souses of price perception were: the actual retail price at selling point, the internal reference price and external reference price. The dimensions of price perception included sacrifice perception, economic value perception, inference, savings perception and price as information perception. Clothing price related behaviors that flowed these dimensions were: low price consciousness, value for money consciousness, price-quality inference, price-prestige inference, sale proneness and price mavenism. An empirical study was conducted to validate the theoretical model. A questionnaire was developed and data were collected from 680 adult women living in Seoul, Korea. Confirmatory factor analysis as well as exploratory factor analysis results showed that theorized price related behaviors were successful classifications.

Fillers in the Hong Kong Corpus of Spoken English (HKCSE)

  • Seto, Andy
    • Asia Pacific Journal of Corpus Research
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    • v.2 no.1
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    • pp.13-22
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    • 2021
  • The present study employed an analytical framework that is characterised by a synthesis of quantitative and qualitative analyses with a specially designed computer software SpeechActConc to examine speech acts in business communication. The naturally occurring data from the audio recordings and the prosodic transcriptions of the business sub-corpora of the HKCSE (prosodic) are manually annotated with a speech act taxonomy for finding out the frequency of fillers, the co-occurring patterns of fillers with other speech acts, and the linguistic realisations of fillers. The discoursal function of fillers to sustain the discourse or to hold the floor has diverse linguistic realisations, ranging from a sound (e.g. 'uhuh') and a word (e.g. 'well') to sounds (e.g. 'um er') and words, namely phrase ('sort of') and clause (e.g. 'you know'). Some are even combinations of sound(s) and word(s) (e.g. 'and um', 'yes er um', 'sort of erm'). Among the top five frequent linguistic realisations of fillers, 'er' and 'um' are the most common ones found in all the six genres with relatively higher percentages of occurrence. The remaining more frequent realisations consist of clause ('you know'), word ('yeah') and sound ('erm'). These common forms are syntactically simpler than the less frequent realisations found in the genres. The co-occurring patterns of fillers and other speech acts are diverse. The more common co-occurring speech acts with fillers include informing and answering. The findings show that fillers are not only frequently used by speakers in spontaneous conversation but also mostly represented in sounds or non-linguistic realisations.

Designing Flexible Curricula for the 21st Century - Case of a Digital Merchandising Course -

  • Kim, Minjeong
    • Fashion & Textile Research Journal
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    • v.23 no.6
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    • pp.691-708
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    • 2021
  • The emerging Fourth Industrial Revolution has triggered fundamental shifts in the fashion industry. Advanced digital technologies are not only reshaping how the fashion supply chains function, but also requisitioning new skill sets for jobs in this industry. A mismatch in required skills between current and future jobs is a critical issue that needs to be addressed in the fashion industry. Similarly, it is imperative that fashion programs in higher education keep pace with the rapid changes disrupting the fashion sector. Nevertheless, the increasing speed and the magnitude of digital transformation make it challenging to keep fashion curricula up to date. This paper presents the case of a Digital Merchandising course. Using the principles of designing flexible curricula and backward design, this Digital Merchandising course was developed to be flexible and responsive to the changing business environment. Building digital intelligence was the central learning goal for students to accomplish. The paper discusses the conceptual development processes for the course and provides, visual examples of major learning assignments, and a variety of digital tools. Fashion educators are encouraged to consider backward design and flexible curricula design guides as complementary tools to the widely used Bloom's taxonomy.

Biodiversity and Enzyme Activity of Marine Fungi with 28 New Records from the Tropical Coastal Ecosystems in Vietnam

  • Pham, Thu Thuy;Dinh, Khuong V.;Nguyen, Van Duy
    • Mycobiology
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    • v.49 no.6
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    • pp.559-581
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    • 2021
  • The coastal marine ecosystems of Vietnam are one of the global biodiversity hotspots, but the biodiversity of marine fungi is not well known. To fill this major gap of knowledge, we assessed the genetic diversity (ITS sequence) of 75 fungal strains isolated from 11 surface coastal marine and deeper waters in Nha Trang Bay and Van Phong Bay using a culture-dependent approach and 5 OTUs (Operational Taxonomic Units) of fungi in three representative sampling sites using next-generation sequencing. The results from both approaches shared similar fungal taxonomy to the most abundant phylum (Ascomycota), genera (Candida and Aspergillus) and species (Candida blankii) but were different at less common taxa. Culturable fungal strains in this study belong to 3 phyla, 5 subdivisions, 7 classes, 12 orders, 17 families, 22 genera and at least 40 species, of which 29 species have been identified and several species are likely novel. Among identified species, 12 and 28 are new records in global and Vietnamese marine areas, respectively. The analysis of enzyme activity and the checklist of trophic mode and guild assignment provided valuable additional biological information and suggested the ecological function of planktonic fungi in the marine food web. This is the largest dataset of marine fungal biodiversity on morphology, phylogeny and enzyme activity in the tropical coastal ecosystems of Vietnam and Southeast Asia. Biogeographic aspects, ecological factors and human impact may structure mycoplankton communities in such aquatic habitats.