• 제목/요약/키워드: Cross-National study

검색결과 4,537건 처리시간 0.036초

각시붕어(Rhodeus uyekii)와 흰줄납줄개(Rhodeus ocellatus) 잡종의 초기생활사 특징 (Early Life History Characteristics of an Induced Hybrid between Rhodeus uyekii and Rhodeus ocellatus)

  • 박재민;한경호
    • 한국수산과학회지
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    • 제52권4호
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    • pp.408-417
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    • 2019
  • This study was conducted to identify taxonomic differences in the characteristics of Rhodeus uyekii and Rhodeus ocellatus during their initial life history via an interspecific hybridization experiment. Hybrids were compared to their parent species, and the findings were used to inform developmental research in commercially useful aquarium fish. The hatching rates of the cross-bred eggs were 75.9% for cross UO (R. uyekii ♀${\times}$R. ocellatus♂) and 71.9% for cross OU (R. ocellatus♀${\times}$R. uyekii♂), which did not differ greatly from the hatching rates of the normal cross-bred group. Backcross experiments resulted in 100% egg mortality during development. Newly hatched larvae of the original hybrid crosses were similar to those of the maternal line, and the color of the egg yolk was similar to that of the paternal line; therefore, the respective traits of the interspecific parents were identifiable within the cross-bred offspring.

CAPS (Cleaved Amplified Polymorphic Sequence) 마커를 적용한 김 교잡육종 기술 개발 (Cross-breeding of Neopyropia spp. (Bangiales, Rhodophyta) Using CAPS (Cleaved Amplified Polymorphic Sequence) Markers)

  • 박은정
    • 한국수산과학회지
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    • 제56권1호
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    • pp.124-132
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    • 2023
  • This study aimed to cross between Korean and Japanese pure lines of Neopyropia strains to establish cross breeding technology and identify a superior variety that harbors the strength of both parents. Four crossing combinations were tried using three methods, resulting in 1,476 single conchocelis colonies. The three co-dominant Cleaved Amplified Polymorphic Sequence (CAPS) markers (EF-1α/Mse I, TOP2/Mse I, car A/ApaL I) were used to distinguish heterozygotic sporophytes and their maternal lines obtained from the inter and intraspecific cross-fertilization within the wild type of Neopyropia strains. Of the 1,476 colonies, 26.9% (218) were heterozygotes obtained from the nuclear CAPS markers. Their maternal line was clearly confirmed using organelle CAPS marker and chimeric thallus was obtained from crossing experiment of Japanese N. yezoensis (♀) and Korean N. yezoensis (♂). The use of CAPS markers improved the efficiency of crossbreeding by quickly screening heterozygotes and maternal lines in the conchocelis phase, which otherwise required pigmentation mutants as genetic markers.

Effect of γ-Irradiation on the Molecular Properties of Bovine Serum Albumin and β-Lcatoglobulin

  • Cho, Yong-Sik;Song, Kyung-Bin
    • BMB Reports
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    • 제33권2호
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    • pp.133-137
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    • 2000
  • To elucidate the effect of oxygen radicals on the molecular properties of proteins, the secondary and tertiary structure and molecular weight size of BSA and ${\beta}$-lactoglobulin were examined after irradiation of proteins at various doses. Gamma-irradiation of protein solutions caused the disruption of the ordered structure of protein molecules as well as degradation, cross-linking, and aggregation of the polypeptide chains. As a model system, BSA and ${\beta}$-lactoglobulin were used as a typical ${\alpha}$-helical and a ${\beta}$-sheet structure protein, respectively. A circular dichroism study showed that the increase of radiation decreased the ordered structure of proteins with a concurrent increase of aperiodic structure content. Fluorescence spectroscopy indicated that irradiation quenched the emission intensity excited at 280 nm. SDS-PAGE and a gel permeation chromatography study indicated that radiation caused initial fragmentation of proteins resulting in a subsequent aggregation due to cross-linking of protein molecules.

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Effect of γ-Irradiation on the Molecular Properties of Myoglobin

  • Lee, Yong-Woo;Song, Kyung-Bin
    • BMB Reports
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    • 제35권6호
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    • pp.590-594
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    • 2002
  • To elucidate the effect of gamma-irradiation on the molecular properties of myoglobin, the secondary and tertiary structures, as well as the molecular weight size of the protein, were examined after irradiation at various irradiation doses. Gamma-irradiation of myoglobin solutions caused the disruption of the ordered structure of the protein molecules, as well as degradation, cross-linking, and aggregation of the polypeptide chains. A SDS-PAGE study indicated that irradiation caused initial fragmentation of the proteins and subsequent aggregation, due to cross-linking of the protein molecules. The effect of irradiation on the protein was more significant at lower protein concentrations. Ascorbic acid protected against the degradation and aggregation of proteins by scavenging oxygen radicals that are produced by irradiation. A circular dichroism study showed that an increase of the irradiation decreased the a-helical content of myoglobin with a concurrent increase of the aperiodic structure content. Fluorescence spectroscopy indicated that irradiation increased the emission intensity that was excited at 280 nm.

Finite-difference Time-domain Study on Birefringence Changes of the Axon During Neural Activation

  • Lee, Jong-Hwan;Kim, Sung-June
    • Journal of the Optical Society of Korea
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    • 제13권2호
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    • pp.272-278
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    • 2009
  • Recently, there has been a growing interest in optical imaging of neural activity because the optical neuroimaging has considerable advantages over conventional imaging. Birefringence of the axon has been reported to change during neural activation, but the neurophysiological origin of the change is still unresolved. This study hypothesizes that the birefringence signal is at least partially attributed to the transient cellular volume change associated with nerve excitation. To examine this hypothesis, we investigated how the intensity of cross-polarized light transmitting through the axon would change as the size of the axon changes. For this purpose, a two-dimensional finite-difference time-domain program was developed with the improvement of the total-field/scattered-field method which reduces numerical noise. The results support our hypothesis in that the computed cross-polarized signals exhibit some agreement with previously-reported birefringence signals.

비자성 연선도체의 단면적을 검출하기 위한 솔레노이드 와전류 센서의 임피던스 해석 및 실험적 연구 (Impedance Analysis and Experimental Study of a Solenoid Eddy Current Sensor to Detect the Cross-sectional Area of Non-ferromagnetic Stranded Conductors)

  • 김성덕;심재명
    • 센서학회지
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    • 제6권2호
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    • pp.87-94
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    • 1997
  • 이 논문에서는 비자성 연선도체의 단면적을 검출하는 솔레노이드 센서의 임피던스 해석이 다루워졌다. 도전체의 전기 자기적 특성들을 검출하기 위하여, 관통형 코일로 비파괴검사 와전류 센서를 선택하였다. Maxwell 방정식을 풀어서 도체봉을 가진 센서의 규격화 임피던스 응답이 모델링되고 그 결과들이 연선에 확장되었다. 연선구조에 미치는 기하학적 성질이 검토되고 수치 해석과 실험결과 또한 주어진다.

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Cross형 초음파 회전모터의 설계에 관한 연구 (A Study on Design of the Cross Type Ultrasonic Rotary Motor)

  • 정현호;박태곤
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2005년도 추계학술대회 논문집 Vol.18
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    • pp.191-192
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    • 2005
  • In this study, the ultrasonic motor which has hollowed cross type stator was designed, and the elastic body of ultrasonic motor was optimized by using a finite element analysis program(ANSYS 9.0). When the length of leg(L) of the elastic body was increased and the width of piezoceramics was decreased, the resonant frequency was increased and the displacement of contact point between the rotor and the stator was increased. However, when the length of the leg was over the 1/3 point of the width of ceramics, the displacement of the contact point was decreased, because the elastic buckle was generated in the leg.

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Effect of gamma-irradiation on the Physicochemical Properties of Hemoglobin

  • Lee, Seung-hwan;Song, Kyung-Bin
    • 한국식품저장유통학회:학술대회논문집
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    • 한국식품저장유통학회 2003년도 제23차 추계총회 및 국제학술심포지움
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    • pp.135.1-135
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    • 2003
  • To elucidate the effect of gamma-irradiation on the molecular properties of hemoglobin, the secondary, tertiary structure, and the molecular weight size of the protein were examined after irradiation at 0.5, 1, 5, and 10 kGy. Gamma-irradiation of hemoglobin solutions caused the disruption of the ordered structure of the protein molecules, as well as degradation, cross-linking, and aggregation of the polypeptide chains. A SDS-PAGE study indicated that irradiation caused initial fragmentation of the proteins and subsequent aggregation due to cross-linking of the protein molecules. The effect of irradiation on the protein was more significant at lower protein concentrations. Ascorbic acid decreased the degradation and aggregation of proteins by scavenging oxygen radicals that were produced by irradiation. A circular dichroism study showed that irradiation decreased the helical content of hemoglobin with a concurrent increase of the aperiodic structure content. Fluorescence spectroscopy indicated that irradiation decreased the emission intensity that was excited at 280 nm.

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스크린을 이용한 직교류 열교환기의 열전달 촉진에 관한 연구 (An Experimental Study on Heat Transfer Enhancement of Cross Flow Heat Exchanger Using Screen)

  • 유성연;장광일;권화길
    • 대한설비공학회:학술대회논문집
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    • 대한설비공학회 2007년도 동계학술발표대회 논문집
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    • pp.185-190
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    • 2007
  • For the successful design of heat exchangers, it is very important to understand local heat transfer characteristics on the circular cylinder of the cross flow heat exchangers. In this study, the heat exchanger using screen is developed to enhance heat transfer. The naphthalene sublimation technique is employed to measure the local heat transfer coefficients in the heat exchanger. The experiments are performed for single circular tube, in-line array tube bank with and without heat transfer promoter. Local Nusselt numbers of single circular tube and tube bank with heat transfer promoter are investigated and compared to those of without heat transfer promoter.

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Solid-state NMR Study on Membrane Protein Structure in Biological Condition

  • Kang, Su-Jin;Lee, Bong-Jin
    • 한국자기공명학회논문지
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    • 제16권2호
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    • pp.103-110
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    • 2012
  • Membrane proteins play a essential role in the biological systems and it is not easy to handle a membrane protein for its structural study. Solid-state NMR (ssNMR) can be a good tool to investigate the structures and dynamics of membrane proteins. In ssNMR, Magic Angle Spinning (MAS) and Cross Polarization (CP) can be utilized to reduce the line-broadening, leading to high resolution and sensitivity in the spectrum. ssNMR, if combined with other spectroscopic methods, can provide us a enough knowledge on structures and dynamics of membrane proteins in biological condition.