• Title/Summary/Keyword: biological distribution

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A Gaussian Beam Light Distribution Model of the Biological Tissue (생체의 가우스빔 광분포모델)

  • 조진호;하영호;이건일
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.25 no.6
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    • pp.654-662
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    • 1988
  • A simple and useful model of light distribution for the biologhical tissue to the Gaussian beam is proposed. This model assumes that the incident Gaussian beam broadens into two Gaussian beams, travelling in the opposite directions as the result of both isotropic scattering and absorption in the tissue. With this assumption, two-dimensional light intensity of each flux as well as the equations of both absorption and scattering have been derived, and the validity of modeling has been confirmed experimentally. Consequently, the results paved a way for easy evaluation of the light distribution in the biological tissue.

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Region- and Neuronal Phenotype-specific Expression of NELL2 in the Adult Rat Brain

  • Jeong, Jin Kwon;Kim, Han Rae;Hwang, Seong Mun;Park, Jeong Woo;Lee, Byung Ju
    • Molecules and Cells
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    • v.26 no.2
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    • pp.186-192
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    • 2008
  • NELL2, a neural tissue-enriched protein, is produced in the embryo, and postembryonically in the mammalian brain, with a broad distribution. Although its synthesis is required for neuronal differentiation in chicks, not much is known about its function in the adult mammalian brain. We investigated the distribution of NELL2 in various regions of the adult rat brain to study its potential functions in brain physiology. Consistent with previous reports, NELL2-immunoreactivity (ir) was found in the cytoplasm of neurons, but not in glial fibrillary acidic protein (GFAP)-positive glial cells. The highest levels of NELL2 were detected in the hippocampus and the cerebellum. Interestingly, in the cerebellar cortex NELL2 was observed only in the GABAergic Purkinje cells not in the excitatory granular cells. In contrast, it was found mainly in the hippocampal dentate gyrus and pyramidal cell layer that contains mainly glutamatergic neurons. In the dentate gyrus, NELL2 was not detected in the GFAP-positive neural precursor cells, but was generally present in mature neurons of the subgranular zone, suggesting a role in this region restricted to mature neurons.

Control of Biofilms in the Drinking Water Distribution System (배·급수관망에서 생물막 제어)

  • Mun, Sungmin;Yoon, Jeyong
    • Journal of Korean Society on Water Environment
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    • v.23 no.1
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    • pp.1-11
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    • 2007
  • The low nutrient environment in drinking water treatment plants and distribution systems cannot to be a good environment for bacterial growth. However, biofilms can be frequently found submerged surface in treatment plants and distribution system. Biofilms in distribution system are harmful, in that they can release organisms, and may cause problems in taste and odor of water. Control of these Biofilms is difficult, and disinfection alone is usually ineffective. Biofilms will not be eliminated from distribution systems by any contemporary technology available now or in the future. Therefore reduction of organic matter, improved disinfection, or a combination of these methods can be useful in controlling distribution system biofilms.

Distribution pattern of Pectinatella magnifica (Leidy, 1851), an invasive species, in the Geum River and the Nakdong River, South Korea

  • Jo, Hyunbin;Joo, Gea-Jae;Byeon, Myeoungseop;Hong, Dong-Gyun;Gim, Jung-Soo;Kim, Ji-Yoon;Choi, Jong-Yun
    • Journal of Ecology and Environment
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    • v.37 no.4
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    • pp.217-223
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    • 2014
  • We conducted a distributional survey of Pectinatella magnifica, an invasive species, in the Geum River and the Nakdong River from July 12 to July 25, 2014. The spacing between the study sites was 10 km along the main channels for the Geum River (n = 12, 120 km) and the Nakdong River (n = 38, 380 km) from the estuarine barrage to upper part of main channel. Pectinatella magnifica was detected along the riparian zone (within 100 m) at each of the study sites. Presence rate of P. magnifica in Geum River and Nakdong River was 25% and 32.6%, respectively. The colony number of P. magnifica at Geum River ($9.5{\pm}3.1colony/m$, n = 3) was over 94 fold higher than that in the Nakdong River ($0.1{\pm}0.1colony/m$, n = 16). The Total length distribution of P. magnifica had a truncated bell shape at each rivers (mean length: $14.0{\pm}1.2cm$ for Geum River (n = 32), and $16.8{\pm}1.4cm$ for Nakdong River (n = 52)). These findings could provide basic information regarding the distribution pattern of P. magnifica in a new invasion area.

First record of the cyanobacterial genus Wilmottia (Coleofasciculaceae, Oscillatoriales) from the South Orkney Islands (Antarctica)

  • Radzi, Ranina;Merican, Faradina;Broady, Paul;Convey, Peter;Muangmai, Narongrit;Omar, Wan Maznah Wan;Lavoue, Sebastien
    • ALGAE
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    • v.36 no.2
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    • pp.111-121
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    • 2021
  • Two cyanobacterial morphotypes isolated from Signy Island, South Orkney Islands, maritime Antarctica were characterised using a polyphasic approach combining morphological, cytological and molecular analyses. These analyses showed that the strains grouped with members of the genus Wilmottia. This genus currently includes three species, W. murrayi, W. stricta, and W. koreana. Both morphotypes analysed in this study were placed within the clade of W. murrayi. This clade showed a well-supported separation from Antarctic and New Zealand strains, as well as strains from other regions. W. murrayi was first described from Antarctica and is now known from several Antarctic regions. Confirmation of the occurrence of W. murrayi at Signy Island significantly extends its known distribution in Antarctica. In addition, a new combination, W. arthurensis, is suggested for Phormidium arthurensis.

A Systematic Study on the Paguroidea (Crustacea: Decapoda) in South Korean Water: Checklist and Geographical Distribution (한국산 집게상과(갑각아강: 십각목)의 분류학적 연구: 종목록 및 지리적 분포)

  • Jung, Jibom;Park, Jin-Ho;Kim, Won
    • Ocean and Polar Research
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    • v.40 no.3
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    • pp.145-160
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    • 2018
  • The Paguroidea is an important group in terms of marine biodiversity. In Korea, paguroids have been studied by many taxonomists and recently we conducted comprehensive taxonomic studies on hermit crabs from the southern part of the Korean Peninsula. As a result, a checklist of 61 species of Paguroidea in South Korean water with their geographical distribution was prepared. Remarks on taxonomy, geographical distribution, and the Korean scientific names of each applicable species were also provided.

SAR Pattern of Biological Objects Contacted with Coaxial Waveguide Antenna Using the FDTD Method (유한 차분법을 이용한 동축 도파관 안테나에 접촉된 생체의 SAR 패턴에 관한 연구)

  • Koo, Sung-Mo;Lee, Chang-Won;Won, Chul-Ho;Cho, Jin-Ho
    • Journal of Biomedical Engineering Research
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    • v.18 no.3
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    • pp.261-266
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    • 1997
  • Nonevasive multifrequency microwave radiometry using coaxial waveguide antenna has been investigated for a homogeneous and four layer human body model. The coupling between coaxial waveguide antenna and a biological object was analyzed by use of the finite-difference time-domain(FDTD) method to obtain the absorbed power patterns in the media. The object studied in this paper was a homogeneous and four-layered lossy medium. The specific absorption rates(SAR) distribution which was corresponding to the temperature distribution was calculated in each region by use of the steady-state response in FDTD method. The SAR pattern of 1.2GHz was compared with that of 1.8GHz.

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Prionolabis crane flies (Diptera: Limoniidae) of Korea

  • Podenas, Sigitas;Park, Sun-Jae;Byun, Hye-Woo;Aukstikalniene, Rasa
    • Journal of Species Research
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    • v.11 no.1
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    • pp.29-37
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    • 2022
  • This study is based on crane fly specimens collected more than 80 years ago in 1938-1939 and preserved at the United States National Museum, Smithsonian Institution, Washington DC, USA. Despite many attempts with a variety of methods, no additional specimens of this genus were captured. This likely means that that this genus is extinct on the Korean Peninsula, or its distribution is restricted to the northern areas of the Democratic People's Republic of Korea (North Korea). The genus Prionolabis Osten Sacken, 1860 with four species, one of them Prionolabis dis(Alexander, 1950) endemic to North Korea, was recorded by Ch. P. Alexander (Alexander, 1938, 1940, 1950). All succeeding papers listing these species were based on these original works without study based on actual specimens. For each species, we present general information on genus, redescriptions of species based on Korean specimens, illustrations of important taxonomical structures, elevation range, period of activity, habitat information, general distribution, and a distribution map for the Korean Peninsula.