• 제목/요약/키워드: biological direction

검색결과 336건 처리시간 0.022초

군산시 공원주변의 동물상과 개발에 따른 생물학적인 영향 및 대책 (Fauna of Some Parks Around Kunsan-City and Biological Impact on the Developments of These Parks)

  • 김세천;윤창호;서홍렬
    • 환경영향평가
    • /
    • 제7권1호
    • /
    • pp.23-34
    • /
    • 1998
  • This study was carried out to survey the fauna of some parks around Kunsan-city and to establish biological impact on the development of those parks. Among the fauna surveyed, insects consist of 74 species in 49 families and 13 orders. The insect fauna was poor, because the environment was made of simple flora and mostly farmland. Fish in the reservoir of Wolmyong-Park consist of 7 species. Among them, Ctenopharyngodon idellus is an exotic species and characterized with its voracious plantfeeding. This fish severely destroyed the habitats and spawning sites of other sympatric fish. For the conservation of non-exotic fish, birds, and mammals in the area, the integrated biological direction would be needed.

  • PDF

야간 근무시의 혈장 멜라토닌의 농도 변화 : 시계 방향과 반시계 방향의 교대근무 비교 (The Nocturnal Changes of Plasma Melatonin Concentrations in Night Shift Workers : Comparison of the Clockwise and Counterclockwise Rotational Shift.)

  • 민순;김미승;임욱빈
    • Journal of Korean Biological Nursing Science
    • /
    • 제2권2호
    • /
    • pp.81-89
    • /
    • 2000
  • To determine the optimal rotational shift system, the effect of the direction of the rotational work shifting on the nocturnal rhythm of plasma melatonin were investigated in nursing students. Two groups of nine volunteers participated as experimental subjects, and two nursing students participated as a control group. The directions of the rotational work shift were as follows: CW(clockwise)-shift were rotated in the direction of day shift(3 days), evening shift(3 days), off duty(1 day) and night shift(5 days), and CCW(conuterclockwise)-shift were done in the reverse direction. Plasma melatonin concentrations was measured by radioimmunoassay. The results were as follows : The plasma melatonin levels were kept low at night and in the following morning in the CW night shift workers, whereas the level started to increase at 05 : 00 hr in two workers of four CCW shift workers. These result suggests that the shift rotation in the CW direction is more acceptable in terms of the adaptation of hormonal rhythms. These results indicate that the CCW rotation of shift work is somewhat better than CCW rotation for the adaptation to shift work on hormonal aspects in nurses.

  • PDF

The Effect of Phenoxymethyl Side Groups on the Liquid Crystal Alignment Behavior of Polystyrene Derivatives

  • Kang, Hyo;Lee, Jong-Chan;Kang, Dae-Seung
    • Macromolecular Research
    • /
    • 제17권7호
    • /
    • pp.506-515
    • /
    • 2009
  • We synthesized a series of polystyrene derivatives containing various side chain terminal moieties, such as phenoxymethyl, 4-methoxyphenoxymethyl, 4-fluorophenoxymethyl, 4-methylphenoxymethyl, and 4-trifluoromethoxyphenoxymethyl groups, using polymer analogous reactions, in order to investigate the effect of the side group on their liquid crystal (LC) alignment behaviors. The polymers containing 4-fluorophenoxymethyl, 4-methylphenoxymethyl, or 4-trifluoromethoxyphenoxymethyl side groups had lower surface energy values and the LC cells fabricated using the unrubbed films of these polymers showed homeotropic LC alignment behavior. The LC cells fabricated using the rubbed films of the polymers containing phenoxymethyl or 4-fluorophenoxymethyl groups showed homogeneous planar LC alignment behavior in which the LCs were aligned perpendicular to the rubbing direction. This homogeneous planar and perpendicular alignment behavior was ascribed to the favorable anisotropic interactions between the LC molecules and the side groups preferentially oriented perpendicular to the rubbing direction.

Screening of Promoters from Metagenomic DNA and Their Use for the Construction of Expression Vectors

  • Han, Sang-Soo;Lee, Jin-Young;Kim, Won-Ho;Shin, Hyun-Jae;Kim, Geun-Joong
    • Journal of Microbiology and Biotechnology
    • /
    • 제18권10호
    • /
    • pp.1634-1640
    • /
    • 2008
  • This study was focused on the screening of valuable genetic resources, such as promoters from metagenome, and describes a promoter trapping system with a bidirectional probe concept, which can select promoters or operons from various biological resources including metagenomic DNA. A pair of reporters, GFP and DsRed, facing the opposite direction without promoters, is an effective system that can function regardless of the direction of inserted promoters. The feasibility of this system was tested for the isolation of constitutively expressed promoters in E. coli from a soil metagenome, resulting in a potential pool of various promoters for practical application. The analyses of structural organization of the trapped genes demonstrated that constitutively expressible promoters in E. coli were broadly distributed within the metagenome, and suggested that some promoters were useful for the construction of expression vectors. Based on these observations, three constitutive promoters were employed in the expression vector system and their potentials for practical application were evaluated in terms of expression level, protein solubility, and effects on host growth.

3차원 Confocal Imaging과 생체 영상 분석 (Three Dimensional Confocal Imaging and Biomedical Image Analysis)

  • 이임걸
    • 대한의용생체공학회:학술대회논문집
    • /
    • 대한의용생체공학회 1995년도 추계학술대회
    • /
    • pp.257-261
    • /
    • 1995
  • Confocal laser scanning microscopy (CLSM)는 기존의 coherent or incoherent microscopic imaging 보다 횡축 방향 (lateral direction)으로 고해상도를 가지며, 층과 층 사이를 구분하는 광축 방향 (axial direction)의 optical sectioning에 의해 샘플의 3D 구조를 고해상도로 영상화함으로써 3D 구조 및 생체 기능 분석을 가능하게 해 준다. 본 논문에서는 CLSM에 의한 3D 영상화 원리와 촛점면 부근에서 얻어지는 광세기 분포, 얻어진 2D slice 영상의 시각화 및 응용에 대해 논의된다.

  • PDF

혈류 방향을 구별하는 연속 초음파 도플러 장치에 관한 연구 (A Study on the Development of CW(Continuous-Wave)Doppler System for measuring Bi-directional Blood Flow Information)

  • 강충신;김영길
    • 대한의용생체공학회:의공학회지
    • /
    • 제8권1호
    • /
    • pp.75-80
    • /
    • 1987
  • With the conventional CW Doppler velocity meter, bl-directional velocities cannot be separated. The new CW Doppler system uses quadrature detection and phase rotation to produce simultaneous independent audio and velocity signals for forward and reverse blood flow direction, is fabricated. Specially, this system shows that phase rotation method for flow direction separation provides easy and satisfactory feature. From in vivo blood flow measurement, we can easily differentiate typical artery flow from vein flow, and measure both velocity characteristics qualitatively.

  • PDF

초음파 섹터 스캐너를 위한 디지털 스캔 변환 기법 (Digital Scan Converter Algorithm for Ultrsound Sector Scanner)

  • 김근호;오정환
    • 대한의용생체공학회:의공학회지
    • /
    • 제17권4호
    • /
    • pp.469-478
    • /
    • 1996
  • In the conventional digital ultrasound scanner, the reflected signal is sampled either in polar coordinates of R-$\theta$ method, or in Cartesian coordinates of uniform ladder algorithm (ULA). The R-$\theta$ scan method necessitates a coordinate transform process which makes hardware complex in comparison with ULA scan mrthoA In spite of this complexity, R-$\theta$ method has a good resolution in ultrasonographic (US) image, since scan direction of the US imaging is a radial direction. In this paper, a new digital scan converter is proposed, which is named the radius uniform ladder algorithm (RULA). The RULA has the rome scan direction as the US scanning in the radial direction and as the display space in the $\theta$ direction. In tllis new approach, sampled points we uniformly distributed in each horizontal line i.n well as in each radial ray so that the data are displayed in the Cartesian coordinates by the 1-D interpolation process. The propped algorithm has an uniform resolution in the periphery and the center field in comparison with equi-angle ULA and equi-interval ULA. To extend the scan angle, concentric square raster sampling (CSRS) is adopted with reduction of discontinuities on the junctions between horizontal scan and vertical scan. The discontinuities are reduced by using the hmction filtering along the $\theta$ direction.

  • PDF

Microstructure of the biological attachment devices in the ladybug Harmonia axyridis (Coleoptera: Coccinellidae)

  • Moon, Myung-Jin;Kim, Hyo-Jeong;Kim, Hoon;Park, Jong-Gu
    • Animal cells and systems
    • /
    • 제16권6호
    • /
    • pp.479-487
    • /
    • 2012
  • Biological attachment device is optimized in insect legs for attachment onto the variety of natural substrate. We have studied the microstructural characteristics of the tarsal appendages in the ladybug Harmonia axyridis using scanning electron microscopy to reveal the attachment system of their legs. The attachment devices are composed of claws and adhesive pads. The claws are connected with pretarsal segment, and their apical diverged hooks are developed to hold rough substrates. In contrast, the adhesive pads have an adhesive function onto smooth surface. The pads are interspersed at the ventral part of each tarsomere, and are composed of two kinds of hairy setae. The discoid tip seta (DtS) has a spoon-shaped endplate usually with a rounded concave structure, whereas the pointed tip seta (PtS) has a pointed tip, usually with a hooked endplate. While the PtS is broadly localized concentrically on the marginal area of both the proximal and distal pads, the DtS can be seen at the central areas of each adhesive pad except for the hind legs. Our findings demonstrate the presence of the direction-dependence pattern of the fibrillar system as well as a functional modification of the tenent setae to achieve proper contact with almost any kind of substrates.