• Title/Summary/Keyword: Morphological evolution

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ANALYZING ISUAL SPECTROPHOTOMETER DATA USING A TWO-COLOR DIAGRAM METHOD

  • CHEN ALFRED BING-CHIH;CHIANG PO-SHIH;HUANG TIAN-HSIANG;KUO CHENG-LING;WANG SHI-CHUN;SU HAN-TZONG;HSU RUE-RoN;CHANG MING-HUI;CHANG YEOU-SHIN;LIU TIE-YUE;MENDE STEPHEN B.;FREY HARALD U.;FUKUNISHI HIROSHI
    • Journal of The Korean Astronomical Society
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    • v.38 no.2
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    • pp.303-306
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    • 2005
  • Transient luminous events (TLEs; sprites, elves, jets and etc.) are lightning-related optical flashes occurring above thunderstorms. Since the first discovery of sprites in 1989, scientists have learned a great deal about the morphological, spectroscopic and electromagnetic characteristics of TLEs through ground and spacecraft campaigns. However, most of the TLE studies were based on events recorded over US High Plains. To elucidate the possible biasing effects, space-borne observations are needed and have their merits. Imager of sprites and Upper Atmospheric Lightning (ISUAL) on the FORMOSAT-2 satellite is the first instrument to carry out a true global measurement of TLEs from a low- earth orbit. In this short paper, we apply a common astronomical data analysis technique, two-color diagram, on the ISUAL spectrophotometer (SP) data. By choosing appropriated bandpasses and converting the measured flux of TLEs into the unit of magnitude, two-color diagrams of TLEs can be constructed. We demonstrate that two-color diagrams, which were constructed from the narrow-band spectrophotometer data, can be used to classify different types of TLEs and trace their temporal evolution. The amount of reddening due to Earth's atmosphere can also be estimated from two-color diagrams assembled from the broad-band spectrophotometer data.

Redescription of Canthocamptus mirabilis Sterba (Copepoda, Harpacticoida), Based on the Topotypic Material from China (중국의 모식산지에서 채집한 갈고리노벌레류 Canthocamptus mirabilis Sterba의 재기재)

  • Chang, Cheon-Young
    • Animal Systematics, Evolution and Diversity
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    • v.17 no.1
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    • pp.1-11
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    • 2001
  • Conthocamptus mirabilis Sterba is redescribed on the basis of the material newly collected from the type locality near Bekijing, China, with an evaluation of the variability of several characters. C. mirabilis possesses the plesiomorphic characters of the round and narrow hyaline membrane and the unmodified outer terminal furcal setae, while it also bears the apomorphic ones of the male-type caudal rami in females and the modified outer terminal setae of male leg 4 exopod. the peculiar dorsal keel ornamented with spinule array on the female's caudal rami is the most significant feature differentiating this species from its relatives of the mirabilis group, which turned out to be a species group of closely related and largely allopatric or parapatric species. Affinities with the allies of the species group are discussed, and the morphological discrepancies differentiating the Japanese population are enumerated.

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Interfacial Microstructure Evolution between Liquid Au-Sn Solder and Ni Substrate (액상 Au-Sn 솔더와 Ni 기판의 계면현상에 대한 고찰)

  • Kim Sung Soo;Kim Jong Hoon;Jeong Sang Won;Lee Hyuck Mo
    • Journal of the Microelectronics and Packaging Society
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    • v.11 no.3 s.32
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    • pp.47-53
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    • 2004
  • Eutectic Au-20Sn(compositions are all in weight percent unless specified otherwise) solder alloys were soldered on the Ni substrate with various time and temperature. The composition, phase identification and morphology of intermetallic compounds(IMC) at the interface were examined using Scanning Electron Microscopy(SEM). There were two types of IMCs, $(Au,Ni)_3Sn_2$ and $(Au,Ni)_3Sn$ at the interface. The transition in morphology of $(Au,Ni)_3Sn_2$ has been observed at $300{\~}400^{\circ}C$. The morphology transition of $(Au,Ni)_3Sn_2$ is due to the decrease of enthalpy of formation of $(Au,Ni)_3Sn_2$ phase and has been explained well by Jackson's parameter with temperature. Because the number of diffusion channel is different at each soldering temperature, IMC thickness is nearly same at all temperature.

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Ultrastructure of Spermatozoa in Pungtungia herzi (돌고기, Pungtungia herzi 정자의 미세구조)

  • 이영환;김구환
    • Development and Reproduction
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    • v.2 no.2
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    • pp.141-148
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    • 1998
  • The fine structure of spermatozoa of Pungtungia herzi was examined with scanning and transmission electron microscopies. The spermatozoa of p. herzi are approximately 37.4 ${\mu}{\textrm}{m}$ in length and a relatively simple cell with a spherical nucleus, a short midpiece and a tail. The acrosome is not present as in most teleost fishes. The ultrastructure of spermatozoa represents typical characteristics of cyprinid spermatozoa including the lateral insertion of flagellum, the organization of centriolar complex in shallow nuclear fossa, and the occurrence and asymmetrical arrangement of mitochondria. In the nuclear envelope and mitochondrion, however there were some morphological differences for their ultrastructure. The nuclear envelope is severely undulated and the shallow nuclear fossa contains two centrioles which are at the angle of some 130$^{\circ}$ each other. The most significant feature can be observed with the mitochondrion; five or more mitochondria, which are shown in primary spermatocyte, fuse to form a single one in the mature spermatozoon. The mitochondrial aspect is different from that of other cyprinid spermatozoa, where their mitochondria have a conventional aspect and never fuse to form a mitochondrial derivative. In terms of sperm evolution the fused mitochondria are regarded as the apomorphic character in comparison with the separate mitochondria. The single mitochondrion is not reported in cyprinid spermatozoon except the case of Rhodeus.

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A Study on Fashion Design Expression Characteristics applied to the concept of the Fold and Ecological Aesthetics (생태미학과 폴드 개념이 적용된 패션디자인 표현특성 연구)

  • Bae, Jungmin
    • Journal of the Korean Society of Costume
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    • v.66 no.5
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    • pp.122-132
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    • 2016
  • In today's society, being considered ecological in fashion design and having a cultural and humanistic approach is important. Using a technological approach, the fold concept was applied to understand and analyze the ecological characteristics of a modern fashion aesthetic design. The concept of 'Ecological Aesthetic Design', which we discuss in this study, is part of human nature, and the design concept is used to consider the relationship between the man and the environment to the design of Victor Papanek. From the perspective of interrelation between the components of an ecosystem, the possibility of the fold's application to ecological aesthetic design can be summarized by wholeness, biodiversity, evolution, homeostasis, and circularity. The concept of the fold is revealed mainly through three types of characteristics: indeterminate complexity, potential continuity, and decentralized interaction relationship. Based on the characteristics of the concept presented earlier, this study conducted a case review by distinguishing contemporary fashion that applied the complex, various, and indeterminate fold concepts into flexible transformation, continuity, and complementary circularity. This study was interpreted from the ecological aesthetic point of view based on the nature of the contingent folds presented before applying modern fashion concepts. It focused on the morphological side, and excluded the material aspects of the case study in order to examine the complex, diverse and content aspects. The result of the study is as follows. The study of the research areas that help the understanding of the changing fashion phenomenonneeds to be encouraged, and there should be a new research category, which can contribute to the ecological aesthetic design concept conversion.

Evaluation of mechanical properties on friction stir lap jointed Al6061/HT590 alloys (겹치기 마찰교반접합 된 Al6061/HT590 합금의 기계적 특성 평가)

  • Kim, Eun-Hye;Lee, Kwang-Jin;Song, Kuk-Hyun
    • Journal of Welding and Joining
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    • v.33 no.2
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    • pp.8-13
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    • 2015
  • This study was carried out to evaluate mechanical properties of the jointed Al6061/HT590 alloys by friction stir welding (FSW). FSW was conducted under the conditions with tool rotating speed of 500 RPM and traveling speed of 300 mm/min., where Ar gas was introduced to prevent the materials from corrosion during the welding process. Electron back-scattering diffraction (EBSD) was used to characterize microstructures such as grain size, misorientation angle and crystal orientation. Evolution of intermetallic compounds in Al6061 during the process were examined in terms of morphology, size and aspect ratio at three distinct zones Al base material, heat affected zone and stir zone, where transmission electron microscope (TEM) was used. It was revealed that FSW gave rise to refinement of grains as well as growth of intermetallic compounds in Al6061. The morphological changes of intermetallic compounds exerted an influence on mechanical properties, resulting in occurrence of fracture in the part of the base material instead of the jointed parts (heat affected zone and stir zone). This study systematically evaluated the microstructural evolutions during the FSW for joining Al6061 with HT590 and their effect on mechanical properties.

Electrodeposition of Silicon in Ionic Liquid of [bmpy]$Tf_2N$

  • Park, Je-Sik;Lee, Cheol-Gyeong
    • Proceedings of the Materials Research Society of Korea Conference
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    • 2011.10a
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    • pp.30.1-30.1
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    • 2011
  • Silicon is one of useful materials in various industry such as semiconductor, solar cell, and secondary battery. The metallic silicon produces generally melting process for ingot type or chemical vapor deposition (CVD) for thin film type. However, these methods have disadvantages of high cost, complicated process, and consumption of much energy. Electrodeposition has been known as a powerful synthesis method for obtaining metallic species by relatively simple operation with current and voltage control. Unfortunately, the electrodeposition of the silicon is impossible in aqueous electrolyte solution due to its low oxidation-reduction equilibrium potential. Ionic liquids are simply defined as ionic melts with a melting point below $100^{\circ}C$. Characteristics of the ionic liquids are high ionic conductivities, low vapour pressures, chemical stability, and wide electrochemical windows. The ionic liquids enable the electrochemically active elements, such as silicon, titanium, and aluminum, to be reduced to their metallic states without vigorous hydrogen gas evolution. In this study, the electrodeposion of silicon has been investigated in ionic liquid of 1-butyl-3-methylpyrolidinium bis (trifluoromethylsulfonyl) imide ([bmpy]$Tf_2N$) saturated with $SiCl_4$ at room temperature. Also, the effect of electrode materials on the electrodeposition and morphological characteristics of the silicon electrodeposited were analyzed The silicon electrodeposited on gold substrate was composed of the metallic Si with single crystalline size between 100~200nm. The silicon content by XPS analysis was detected in 31.3 wt% and the others were oxygen, gold, and carbon. The oxygen was detected much in edge area of th electrode due to $SiO_2$ from a partial oxidation of the metallic Si.

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Genome Mapping Technology And Its Application In Plant Breeding (작물 육종에서 분자유전자 지도의 이용)

  • 은무영
    • Proceedings of the Botanical Society of Korea Conference
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    • 1995.07a
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    • pp.57-86
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    • 1995
  • Molecular mapping of plant genomes has progressed rapidly since Bostein et al.(1980) introduced the idea of constructing linkage maps of human genome based on restriction fragment length polymorphism (RFLP) markers. In recent years, the development of protein and DNA markers has stimulated interest for the new approaches to plant improvement. While classical maps based on morphological mutant markers have provided important insights into the plant genetics and cytology, the molecular maps based on molecular markers have a number of inherent advatages over classical genetic maps for the applications in genetic studies and/or breeding schemes. Isozymes and DNA markers are numerous, discrete, non-deleterious, codominant, and almost entirely free of environmental and epistatic interactions. For these reasons, they are widely used in constructing detailed linkage maps in a number of plant species. Plant breeders improve crops by selecting plants with desirable phenotypes. However a plant's phenotyes is often under genetic control, positioning at different "quantitative trait loci" (QTLs) together with environmental effects. Molecular maps provide a possible way to determine the effect of the individual gene that combines to produce a quantitative trait because the segregation of a large number of markers can be followed in a single genetic cross. Using market-assisted selection, plants that contain several favorable genes for the trait and do not contain unfavourable segments can be obtained during early breeding processes. Providing molecular maps are available, valuable data relevant to the taxonomic relationships and chromosome evolution can be accumulated by comparative mapping and also the structural relationships between linkage map and physical map can be identified by cDNA sequencing. After constructing high density maps, it will be possible to clone genes, whose products are unknown, such as semidwarf and disease resistance genes. However, much attention has to be paid to level-up the basic knowledge of genetics, physiology, biochemistry, plant pathology, entomology, microbiology, and so on. It must also be kept in mind that scientists in various fields will have to make another take off by intensive cooperation together for early integration and utilization of these newly emerging high-techs in practical breeding. breeding.

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Comparative Genomics Reveals the Core and Accessory Genomes of Streptomyces Species

  • Kim, Ji-Nu;Kim, Yeonbum;Jeong, Yujin;Roe, Jung-Hye;Kim, Byung-Gee;Cho, Byung-Kwan
    • Journal of Microbiology and Biotechnology
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    • v.25 no.10
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    • pp.1599-1605
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    • 2015
  • The development of rapid and efficient genome sequencing methods has enabled us to study the evolutionary background of bacterial genetic information. Here, we present comparative genomic analysis of 17 Streptomyces species, for which the genome has been completely sequenced, using the pan-genome approach. The analysis revealed that 34,592 ortholog clusters constituted the pan-genome of these Streptomyces species, including 2,018 in the core genome, 11,743 in the dispensable genome, and 20,831 in the unique genome. The core genome was converged to a smaller number of genes than reported previously, with 3,096 gene families. Functional enrichment analysis showed that genes involved in transcription were most abundant in the Streptomyces pan-genome. Finally, we investigated core genes for the sigma factors, mycothiol biosynthesis pathway, and secondary metabolism pathways; our data showed that many genes involved in stress response and morphological differentiation were commonly expressed in Streptomyces species. Elucidation of the core genome offers a basis for understanding the functional evolution of Streptomyces species and provides insights into target selection for the construction of industrial strains.

Study of the Rheological Properties of a Fermentation Broth of the Fungus Beauveria bassiana in a Bioreactor Under Different Hydrodynamic Conditions

  • Nunez-Ramirez, Diola Marina;Medina-Torres, Luis;Valencia-Lopez, Jose Javier;Calderas, Fausto;Lopez-Miranda, Javier;Medrano-Roldan, Hiram;Solis-Soto, Aquiles
    • Journal of Microbiology and Biotechnology
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    • v.22 no.11
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    • pp.1494-1500
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    • 2012
  • Fermentation with filamentous fungi in a bioreactor is a complex dynamic process that is affected by flow conditions and the evolution of the rheological properties of the medium. These properties are mainly affected by the biomass concentration and the morphology of the fungus. In this work, the rheological properties of a fermentation with the fungus Beauveria bassiana under different hydrodynamic conditions were studied and the rheological behavior of this broth was simulated through a mixture of carboxymethyl cellulose sodium and cellulose fibers (CMCNa-SF). The bioreactor was a 10 L CSTR tank operated at different stir velocities. Rheological results were similar at 100 and 300 rpm for both systems. However, there was a significant increase in the viscosity accompanied by a change in the consistence index, calculated according to the power law model, for both systems at 800 rpm. The systems exhibited shear-thinning behavior at all stir velocities, which was determined with the power law model. The mixing time was observed to increase as the cellulose content in the system increased and, consequently, the efficiency of mixing diminished. These results are thought to be due to the rheological and morphological similarities of the two fungal systems. These results will help in the optimization of scale-up production of these fungi.