• Title/Summary/Keyword: Morphological Evolution

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Far-infrared Study of Supernova Remnants in the Large Megellanic Cloud

  • Kim, Yesol;Koo, Bon-Chul;Seok, Ji Yeon
    • The Bulletin of The Korean Astronomical Society
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    • v.38 no.1
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    • pp.53-53
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    • 2013
  • We present preliminary results of far-infrared(FIR) study of the supernova remnant(SNR)s in the Large Magellanic Cloud using the Herschel HERITAGE (HERschel Inventory of The Agents of Galaxy Evolution) data set. HERITAGE provides FIR data covering the entire LMC at 100,160, 250, 350, and 500 um. In order to confirm FIR emission associated with SNRs, we refer to Magellanic Cloud Emission-Line Survey (MCELS) H-alpha & SII data, Spitzer surveying the Agents of a Galaxy's Evolution (SAGE) Multiband Imaging Photometer (MIPS) 24um & 70um data, Chandra Supernova Remnants Catalog, and ATCA 4.8GHz continuum images of Dickel et al. (2005). Among 47 SNRs in the LMC, 7 SNRs show associated FIR emission. We present multi-wavelength view of 5 SNRs; DEM L249, N49, N63A, N132D, and the SNR in N4. N49 and N132D show morphological correlation in FIR and X-ray, suggesting that the FIR emission is from dust grains collisionally heated by X-ray emitting plasma. The FIR emission of N63A resembles H-alpha emission, which implies that the FIR line radiation could be dominant. The FIR images of the rest two objects, DEM L249 and SNR in N4, show no correlation to the other-waveband images.

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Galaxy Ecology: The Role of Neighbors

  • Moon, Jun-Sung;Yoon, Suk-Jin
    • The Bulletin of The Korean Astronomical Society
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    • v.39 no.1
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    • pp.44.2-44.2
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    • 2014
  • We investigate the influence of neighboring galaxies as a component of the local environment. Based on the SDSS data release 7 and the KIAS value-added galaxy catalog, we have constructed a galaxy pair catalog by matching each galaxy with its nearest and its most tidally-influential neighbor. In particular, we examine the star formation rate (SFR) derived from their optical u-r color and $H{\alpha}$ emission as functions of neighbor's distance, tidal force, and morphological type. The results are as follows. (1) The $H{\alpha}$-based SFR of galaxies with close companions is enhanced by up to a factor of three regardless of neighbor's morphology, when compared to isolated counterparts. (2) The mean u-r color of galaxies along with early-type galaxies is redder than that of isolated ones, yet bluer with late-types. (3) The galaxies with late-type companions mostly show higher SFR than those with early-types. The results suggest that the role played by neighboring galaxies are two-fold; (a) the tidal effect on the shorter scale of time and of distance, and (b) the hydrodynamic effect on the longer scale.

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A genetic approach to comprehend the complex and dynamic event of floral development: a review

  • Jatindra Nath Mohanty;Swayamprabha Sahoo;Puspanjali Mishra
    • Genomics & Informatics
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    • v.20 no.4
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    • pp.40.1-40.8
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    • 2022
  • The concepts of phylogeny and floral genetics play a crucial role in understanding the origin and diversification of flowers in angiosperms. Angiosperms evolved a great diversity of ways to display their flowers for reproductive success with variations in floral color, size, shape, scent, arrangements, and flowering time. The various innovations in floral forms and the aggregation of flowers into different kinds of inflorescences have driven new ecological adaptations, speciation, and angiosperm diversification. Evolutionary developmental biology seeks to uncover the developmental and genetic basis underlying morphological diversification. Advances in the developmental genetics of floral display have provided a foundation for insights into the genetic basis of floral and inflorescence evolution. A number of regulatory genes controlling floral and inflorescence development have been identified in model plants such as Arabidopsis thaliana and Antirrhinum majus using forward genetics, and conserved functions of many of these genes across diverse non-model species have been revealed by reverse genetics. Transcription factors are vital elements in systems that play crucial roles in linked gene expression in the evolution and development of flowers. Therefore, we review the sex-linked genes, mostly transcription factors, associated with the complex and dynamic event of floral development and briefly discuss the sex-linked genes that have been characterized through next-generation sequencing.

Molecular Phylogeny of Syngnathiformes Fishes Inferred from Mitochondrial Cytochrome b DNA Sequences (실고기목 어류 (Syngnathiformes)의 분자계통학적 분류)

  • KOH Beom Seok;SONG Choon Bok
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.37 no.5
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    • pp.405-413
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    • 2004
  • The previous morphology-based taxonomic frameworks within the family Syngnathidae had emphasized the significance of the male brood pouch and reproductive biology in defining the group. However, several different hypotheses had been proposed by different investigators. This study has been carried out to determine the phylogenetic relationships among 19 species belonging to the order Syngnathiformes with three Gasterosteiformes species as outgroup taxa by using the mitochondrial cytochrome b DNA sequences. Phylogenetic analyses based on neighbor-joining distance, maximum parsimony, minimum evolution and maximum likelihood method strongly supported that the family Syngnathidae, the suborder Syngnathoidei and the order Syngnathiformes were all monophyletic group. Although much of previous morphological analyses were supported by our molecular data, there were some significant discrepancies between molecular and morphological work. Such an interesting result was that the weedy seadragon (Phyllopteryx taeniolatus) strongly grouped together with the New Zealand pot-belly seahorse (Hippocampus abdominalis). Considering the markedly different brooding structure between them, this unexpected result might be explained whether by multiple independent origins of brooding structure or by hybridization between the female Hippocampus and other syngnathid species having individual membranous egg compartment. In addition, the suborder Aulostomoidei was paraphyletic group because the shrimpfish (Aeliscus strigatus), belonging to the family Centriscidae, always grouped together with the family Syngnathidae as a sister taxon.

Taxonomic Revision of Notohymena gangwonensis (Protozoa: Ciliophora), with Notes on Its Cortical Granules and Scanning Electron Micrographs

  • Moon, Ji Hye;Kim, Kang-San;Chae, Kyu Seok;Min, Gi-Sik;Jung, Jae-Ho
    • Animal Systematics, Evolution and Diversity
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    • v.36 no.2
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    • pp.113-122
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    • 2020
  • From a moss sample, we isolated and identified Notohymena gangwonensis Kim et al., 2019 based on morphological and molecular data. The moss and type population has completely identical 18S rRNA (nuclear small subunit ribosomal RNA) gene sequences and both are highly similar in morphological and morphometric attributes, except for the diameter and arrangement of the cortical granules. Thus, we reexamined the type materials(i.e., micrographs and gDNA) and resulted in finding mistakes made by the authors of the species. Based on these data and supporting materials newly obtained (i.e., internal transcribed spacer [ITS] 1, ITS2, 5.8S, and partial 28S rDNA sequences, and scanning electron micrographs), we provide improved diagnosis of the species to clarify its identity. In addition, a key for Notohymena species is provided.

Epicranial Bony System of Six Species in Family Cynoglossidae (Pisces, Pleuronectiformes) from Korea (한국산 참서대과 Cynoglossidae 어류 6종의 상두개골계(epicranical bony system))

  • Choi, Youn;Kim, Ik-Soo
    • Animal Systematics, Evolution and Diversity
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    • v.11 no.3
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    • pp.329-334
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    • 1995
  • The epicranial bony system of the six species of the family Cynoglossidae were examined based on the specimens collected from the coast of Korea from 1992 to 1994. They were divided into four groups by the morphological features of epicranial bony system as follow: 1. Paraplagusia japonica, 2. Cynoglossus joyneri and C. robustus, 3. C. semilaeuis and C. abbreuiatus, and 4. C. interruptus. Among them, P japonica showed the most derived character in the erisma and frontal elements of the epicranial bony system. And it was remarked that the number of proximal radials supporting erisma show much differences among the species. It is discussed that the morphological differences in the epicranial bony system are significant character for interspecific relationships in family Cynoglossidae.

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Zoeal Stages and Megalopa of Hemigrapsus penicillagtus(De Haan, 1835) (Decapoda, BRachyura, Grapsidae) Reared in the Laboratory) (풀게 Hemigrapsus penicillatus(게아목, 바위게과)의 zoea 및 megalopa 유생기)

  • Sang-Gu Hwang;Chang-Hyun Kim
    • Animal Systematics, Evolution and Diversity
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    • v.11 no.3
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    • pp.389-408
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    • 1995
  • The complete larval development of Hemigrapsus penicillatus(De Haan, 1835) from hatching to first crab stage was obtained by culture in the laboratory. Under culture conditions with salinity 33.3% , temperature $25^{\circ}C$, and photophase 14/10 h light/dark, the megalopa and the first crab instar were attained in minimum of 18 and 29 days after hatching respectively. Five zoeal stages and a megalopal stage are described and illustrated in detail. Morphological characters of H. penicillatus larvae were compared with those of other members within the subfamily Varuninae. Morphological differences among H. penicillatus, H. sanguineus and H. sinensis in megalopal stage are tabulated.

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Study on the eletronic absorption and surface morphology of phthalocyanine double layer thin films

  • Heo, Il-Su;Ryu, Il-Hwan;Hong, Da-Jeong;Im, Sang-Gyu
    • Proceedings of the Korean Vacuum Society Conference
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    • 2011.02a
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    • pp.337-337
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    • 2011
  • The elecronic absorption and surface morphology evolution of two types of molecular double layer thin films, copper phthalocyanine(CuPc) layer deposited on top of chloro[subphtalocyaninato]boron(III) (SubPc) layer, denoted as SubPc/CuPc, and vice versa, at various thicknesses were invertigated using ultraviolet(UV)-visible spectroscopy and atomic force microscopy (AFM). Both types of double layer structures showed similar broadened absorption patterns in UV-visible region which were well consistent with fitted spectra by a simple linear combination of single layer absorption spectra of two materials. In contrast, the surface morphology of double layer structures was dependent on the order of deposition. For CuPc/SubPc structures, the surface morphology was characterized by elongated grains, characteristic of SubPc thin films, indicating the morphological influence of underlying CuPc layer on subsequent SubPc layer was not large. For SubPc/CuPc structures, however, the underlying SubPc layer acted as a morphological template for the subsequently deposited CuPc layer. It was also observed that the grain size of CuPc layer varied by the thickness of underlying SubPc layer.

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Phylogeny and systematics of Crossosomatales as inferred from chloroplast atpB, matK, and rbcL sequences

  • Oh, Sang-Hun
    • Korean Journal of Plant Taxonomy
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    • v.40 no.4
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    • pp.208-217
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    • 2010
  • Crossosomatales is a recently recognized order in the rosid II clade with about 64 species in eight morphologically distinct families that have been previously classified in as many as 15 other orders. Phylogenetic relationships among the families and genera within Crossosomatales were investigated using chloroplast atpB, matK, and rbcL sequences employing maximum parsimony, maximum likelihood, and Bayesian methods. The phylogenetic framework was used to examine the patterns of morphological evolution and synapomorphies for subclades within Crossosomatales. The combined data with representative species from all genera in the order strongly supported monophyly of Crossosomatales. Strong support was found for the families in the Southern Hemisphere, in which Aphloiaceae is sister to the clade of (Geissolomataceae, (Ixerbaceae + Strasburgeriaceae)). The sister relationship between the Southern Hemisphere clade and families distributed primarily in the Northern Hemisphere was also supported. As in the previous studies, following relationships were found within the Northern Hemisphere clade: Staphyleaceae is sister to a clade of (Guamatelaceae, (Stachyuraceae + Crossosomataceae)). The pattern analysis indicates that evolutionary pattern of morphological characters is complex, requiring multiple changes within Crossosomatales. Several reproductive traits, such as inflorescence, aril, stigma, and conspicuous protrusion from pollen aperture, corroborate the molecular phylogeny.

Study on Electronic Absorption and Surface Morphology of Double Layer Thin Films of Phthalocyanines

  • Park, Gyoo-Soon;Heo, Il-Su;Ryu, Il-Hwan;Yim, Sang-Gyu
    • Bulletin of the Korean Chemical Society
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    • v.32 no.3
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    • pp.943-946
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    • 2011
  • The electronic absorption and surface morphology evolution of two types of molecular double layer thin films, copper phthalocyanine (CuPc) layer deposited on chloro[subphthalocyaninato]boron(III) (SubPc) layer, denoted as SubPc/CuPc, and vice versa, with various thicknesses were investigated using ultraviolet (UV)-visible spectroscopy and atomic force microscopy (AFM). Both types of double layer structures showed similar broadened absorption patterns in the UV-visible region that were consistent with the fitted spectra following simple linear combination of the single layer absorption spectra of the two materials. In contrast, the surface morphology of double layer structures was dependent on the order of deposition. For the CuPc/SubPc structures, surface morphology was characterized by elongated grains, which are characteristic of SubPc thin films, indicating that the morphological influence of the underlying CuPc layer on the subsequent SubPc layer was not large. For the SubPc/CuPc structures, however, the underlying SubPc layer acted as a morphological template for the subsequently deposited CuPc layer. It was also observed that the grain size of the CuPc layer varied according to the thickness of the underlying SubPc layer.